Citation

Last Updated: October 2026

This policy establishes ETFLIN's requirements for citing sources, preparing reference lists, verifying bibliographic information, and maintaining ethical citation practices. Accurate and appropriate citation is essential to scholarly communication because it acknowledges intellectual contributions, supports scientific claims, enables readers to verify information, and preserves the traceability of the scholarly record.

ETFLIN adopts the Vancouver citation style across its journals, with journal-specific formatting details implemented through the ETFLIN Vancouver reference style. Authors must ensure that citations and references are accurate, relevant, complete, and consistent with the requirements described in this policy.

General Principles

Authors must appropriately cite the sources of information, ideas, methods, data, interpretations, and other scholarly contributions that originate from work other than their own. Citations should enable readers to identify the source being referenced and understand how it supports the statement, method, or finding discussed in the manuscript.

References must be selected according to their relevance, reliability, and relationship to the claims being made. Authors should cite sources that directly support the information presented and should avoid adding references merely to increase the length of the reference list or create an appearance of extensive literature coverage.

Where appropriate, authors should prioritize original research publications when citing specific findings, methods, or data. Review articles may be useful for summarizing a field or providing broader context, but they should not automatically replace relevant primary sources when those sources are available and necessary to substantiate a particular claim.

Authors must not cite a source solely because it appears in another article's reference list. Whenever practicable, the original source should be consulted and verified before it is cited. If an original source cannot reasonably be obtained and a secondary source must be used, the authors should make the limitation clear where necessary and avoid implying that they independently examined the original work.

The ICMJE Recommendations on References similarly require accurate referencing, encourage direct citation of original research where appropriate, and caution against citations used for self-promotion or to support claims that the cited material does not substantiate.

Citations should be sufficient to support the scholarly argument but should not be unnecessarily repetitive. Widely established facts may not require repeated citations in every sentence, whereas specific empirical claims, numerical values, disputed interpretations, and statements based on previous research should have appropriate supporting references.

Vancouver Citation Style

ETFLIN uses a numbered Vancouver citation system. References must be numbered consecutively according to their first appearance in the manuscript, using Arabic numerals enclosed in parentheses rather than square brackets.

Each source receives one reference number when it is first cited. Subsequent citations to the same source must use the original number rather than creating a new entry. Where multiple sources support a statement, their reference numbers should be grouped and presented in numerical order according to the ETFLIN Vancouver style.

References cited in tables, figure legends, appendices, and supplementary materials must follow the same numbering sequence as the main manuscript. A reference cited only in a table or figure must be numbered according to the sequence established by the first mention of that table or figure in the text, rather than through a separate numbering system.

The final reference list must appear at the end of the manuscript and follow the numerical order of citation. Every numbered in-text citation must correspond to an identifiable reference entry, and every entry in the reference list must be cited in the manuscript unless a specific publication format expressly permits otherwise.

Authors must not renumber references manually without checking the entire manuscript. When references are added, removed, or reordered during revision, all affected in-text citations, tables, figures, supplementary materials, and reference-list entries must be updated consistently.

Accuracy and Verification of References

Authors are responsible for the accuracy of every reference included in a manuscript. The existence of a reference in a citation manager, search result, database, or another article does not independently establish that its bibliographic information is correct or that it supports the cited claim.

Before submission, authors must verify the information necessary to identify each source, including the author or issuing organization, title, publication details, year, volume, issue, page range or article number where applicable, and DOI or other persistent identifier where available.

References should be checked against the original publication or an authoritative bibliographic record. For biomedical publications, PubMed and the NLM Catalog can assist with verifying indexed publications and standardized journal titles. Other disciplines may require the relevant disciplinary database, publisher record, repository, or issuing institution.

A DOI must resolve to the intended publication and must not be copied from an unrelated source. Authors should not assume that a DOI is correct merely because it appears in a reference generated by software.

Where information cannot be verified, authors must investigate the discrepancy and correct the reference before submission. Missing bibliographic information must not be invented to make an entry appear complete. If a required element is genuinely unavailable, the reference should be prepared according to the applicable ETFLIN style requirements for that source type.

Reference management software may be used to organize and format citations. ETFLIN provides a customized Vancouver style for users of supported reference management workflows. However, automated formatting does not remove the author's responsibility to inspect the resulting references for accuracy, completeness, and consistency.

Relevance and Appropriate Selection of Sources

Every citation must have a defensible scholarly purpose. The cited source should support the statement being made, provide relevant methodological information, document the origin of a dataset or concept, or otherwise contribute meaningfully to the manuscript's scientific argument.

Authors should avoid citing sources that are unrelated to the claim, insufficiently reliable for the purpose, or included primarily to increase the visibility or citation metrics of a particular author, editor, reviewer, institution, journal, or publisher.

A citation must not be used to imply that a source supports a conclusion when the source actually reports a different result, expresses uncertainty, or discusses a materially different context. Authors should assess the original findings and limitations before deciding how to characterize them.

Where studies report conflicting results, authors should represent the disagreement fairly and cite relevant evidence rather than selecting only sources that support a predetermined conclusion. Reviews of existing research should not deliberately omit significant contrary findings in a manner that creates a misleading account of the evidence.

Authors should use the most relevant and reliable sources available. A publication's age, journal prestige, citation count, or inclusion in an indexing database does not automatically establish that it is appropriate for a particular claim.

Authors should avoid citing predatory or pseudo-journals and should exercise appropriate judgment when assessing the credibility of a publication source, consistent with the ICMJE Recommendations on References.

Citation of Original Research and Secondary Sources

When citing a specific experimental result, dataset, analytical method, or original observation, authors should cite the original research publication whenever it is available and relevant.

Review articles and other secondary sources may appropriately be cited for general overviews, theoretical frameworks, or syntheses of a body of evidence. However, they should not be used to attribute a finding directly to an original study without confirming that the original study supports that finding.

When the original source cannot reasonably be accessed, authors may cite an appropriate secondary source, provided that the citation accurately represents the information actually consulted. The manuscript must not imply that the original source was examined when it was not.

A secondary citation should not be used to conceal uncertainty regarding the origin, accuracy, or interpretation of a claim. If an important statement cannot be verified from an adequate source, authors should revise or omit the statement rather than rely on an unverified citation chain.

Self-Citation and Citation Manipulation

Authors may cite their own previously published work when it is directly relevant to the manuscript. Self-citation is appropriate when it establishes the background, documents prior methods or findings, identifies an earlier stage of a research program, or provides another legitimate scholarly connection.

However, self-citation must not be excessive, irrelevant, or used to inflate an author's citation record. Authors should not preferentially cite their own work when more relevant sources would better support the statement.

The same principles apply to citations involving a journal, its editors, editorial board members, reviewers, or other affiliated individuals. Citations must be selected according to scholarly relevance rather than the interests of the individuals or organizations being cited.

Authors must not add references solely because an editor or reviewer requests citations that are unrelated to the manuscript's scientific content. Conversely, a request to cite genuinely relevant literature is not inherently improper merely because the suggested source was authored by the person making the request.

Editors and reviewers must not use their positions to require irrelevant citations for the purpose of improving personal, institutional, or journal citation metrics. Citation recommendations should have a clear scholarly justification.

These principles are consistent with COPE's guidance on citation manipulation, which distinguishes legitimate citation recommendations from practices intended primarily to manipulate citation metrics.

Concerns involving systematic or intentional citation manipulation may be referred for further assessment under ETFLIN's applicable publication ethics procedures.

Direct Quotations, Paraphrasing, and Attribution

Direct quotations must reproduce the source accurately and must be clearly distinguished from the author's own text. Quoted material should be used only when the original wording is necessary or particularly relevant to the argument. Where required by the source type and citation format, authors should provide page numbers or other precise location information.

Paraphrased material must be expressed in the author's own words while preserving the meaning of the cited source. Merely changing a few words or rearranging sentence structure does not remove the obligation to acknowledge the original source.

Citations must be placed close enough to the relevant statement to make clear which information they support. A citation placed at the end of a long paragraph should not be assumed to substantiate every claim in that paragraph if the relationship between the source and individual statements is unclear.

Authors must distinguish their own interpretation from the conclusions of previously published research. When a paragraph combines findings from several sources with the author's own analysis, citations should be positioned so that the origins of the different claims remain clear.

The attribution of previously published words, ideas, data, or images must be handled according to the relevant scholarly and copyright requirements. Questions concerning plagiarism or the unauthorized reuse of third-party material are assessed under ETFLIN's applicable ethical and copyright procedures rather than being resolved solely through citation formatting.

Reference List and Bibliographic Formatting

The reference list must follow the ETFLIN Vancouver citation style. Each reference must contain the identifying information appropriate to its publication type and should be formatted consistently throughout the manuscript.

Journal Articles

Journal article references should include the authors, article title, journal title, publication year, volume, issue and page range or article number where applicable, and DOI where available.

Article titles should follow sentence case. Journal titles may be provided in their full form or in a standardized abbreviated form, but the format should be applied consistently throughout the reference list. Where abbreviated journal titles are used, authors should use an established abbreviation rather than inventing one.

The standard format is:

Author(s). Article title. Journal title or standardized abbreviation. Year;Volume(Issue):Page range or article number. DOI where available.

For example, a reference based on an article published under a continuous publication model may contain a volume and an article identifier rather than a conventional page range or issue number. Authors should include the bibliographic elements that actually apply to the cited publication and must not invent missing issue or pagination information.

The National Library of Medicine's Citing Medicine guidance for journal articles provides additional reference-formatting guidance that may assist authors in identifying appropriate bibliographic elements.

Articles Published Online Before Issue Assignment

Articles published online before final assignment to a volume or issue must be cited using the information available in the authoritative publication record.

Where a DOI and an online publication date are available but volume, issue, or page information has not yet been assigned, authors should not fabricate those elements. The reference should identify the article using its available bibliographic details and persistent identifier.

Once the final bibliographic information becomes available, authors should update the reference where necessary before submission or during revision.

Books

Book references should identify the author or responsible organization, book title, edition where applicable, place of publication, publisher, and year of publication.

Book titles should follow the title capitalization convention specified by ETFLIN. Edition information should be included where relevant, particularly when different editions contain materially different content.

The standard format is:

Author(s). Book title. Edition. Place of publication: Publisher; Year.

Where an electronic book has a DOI or another persistent identifier and the identifier is relevant to locating the cited edition, it should be included according to the applicable style requirements.

Chapters in Edited Books

A chapter in an edited book must be cited as an individual contribution rather than as though it were a standalone book.

The reference should identify the chapter author or authors, chapter title, book editors, book title, edition where applicable, publication details, and page range or other available location information.

The standard format is:

Chapter author(s). Chapter title. In: Editor(s), editor(s). Book title. Edition. Place of publication: Publisher; Year. p. Page range.

The chapter title should follow the citation conventions applied to article titles, while the book title should follow the applicable book-title convention. Authors must ensure that the chapter's bibliographic details correspond to the actual edition consulted.

Websites and Online Documents

References to webpages and online documents must provide sufficient information for readers to identify the source and locate the specific material cited.

The reference should include the responsible author or organization, webpage or document title, publication or update date where available, access date, and URL. Additional publisher or website information should be included where relevant and supported by the source.

The standard format is:

Author or organization. Title of webpage or document [Internet]. Publisher or website information where applicable; publication or update date [cited Year Month Day]. Available from: URL.

For online material that changes over time, the access date is required to indicate when the cited content was consulted. Authors should provide a direct link to the relevant page or document rather than a general homepage where a specific source is available.

URLs must be checked before submission. Where an online document also has a DOI or another persistent identifier, the most suitable identifier should be included according to the source type and ETFLIN style requirements.

A website citation does not automatically establish that the source is authoritative or suitable for supporting a scientific claim. Authors remain responsible for evaluating the reliability, relevance, and currency of online information.

Preprints

Preprints may be cited when they are relevant to the manuscript, but their publication status must be clearly identified. A preprint has not necessarily undergone formal peer review, and its findings should not be represented as though they have received the same evaluation as a peer-reviewed publication.

The reference should identify the authors, title, preprint server, publication or posting year, and DOI or stable URL where available. The entry must clearly indicate that the work is a preprint.

If a peer-reviewed version of the same work is available and is appropriate for the claim being supported, authors should generally cite the published version. If both versions are necessary to describe the history of the work or a material difference between them, the relationship should be made clear.

Authors must not omit the preprint designation or cite a preprint in a way that misleads readers about its publication status. When a preprint has been revised or replaced, the cited version should be identifiable.

Datasets and Research Software

When research data or software are cited as scholarly sources, the reference should identify the creators or responsible organization, dataset or software title, version or release where applicable, repository or distribution source, year, and DOI or other persistent identifier where available.

A dataset should be cited using the identifier of the specific record or version that supports the reported research. Software should be identified sufficiently to distinguish the version used in the study from later releases.

Citations to datasets and software should be included in the reference list when they are necessary to document the research methods, analytical procedures, or evidence used in the manuscript.

The citation of a dataset does not replace the requirements governing its availability or deposition. Likewise, a link to software does not establish that it was used in the reported analysis unless that use is accurately described in the manuscript.

Conference Proceedings and Abstracts

Conference papers, proceedings, and abstracts must be identified according to the nature of the material being cited. The reference should distinguish a full published paper from an abstract, presentation, or other contribution where the distinction is relevant to evaluating the evidence.

The reference should include the author or authors, title of the contribution, conference or proceedings title, publication details, year, page range or article identifier where applicable, and a DOI or stable URL when available.

Authors should not cite a conference abstract as though it were a complete peer-reviewed research report. When a full article reporting the same work is available, authors should normally use the full article for claims that require detailed methods or complete results.

Theses, Dissertations, and Reports

References to theses, dissertations, institutional reports, technical reports, and similar materials must identify the author or issuing organization, title, document type where necessary, institution or publisher, year, and repository or stable location where available.

Where a report has a persistent identifier or an official document number, that information should be included. If a document is unpublished or available only through a restricted institutional source, its status and access conditions must be represented accurately.

Authors should consider whether a report or thesis is the most appropriate source for the claim being supported and whether a peer-reviewed publication containing the relevant findings is available.

Guidelines, Standards, and Official Documents

Scientific guidelines, technical standards, consensus statements, and official documents should be cited using the bibliographic information provided by the issuing organization or publisher.

The reference must identify the responsible organization or author, title, version or edition where relevant, publication or update year, and DOI or stable URL where available. Authors should ensure that the cited version is the one actually used or discussed in the manuscript.

Where a guideline has been updated or superseded, authors should avoid presenting an earlier version as current without explaining why that version is relevant to the research.

Unpublished Material and Personal Communications

References to unpublished or non-retrievable material require particular care because readers may not be able to independently access or verify the information.

Manuscripts that have been accepted for publication but are not yet available may be cited as "in press" or "forthcoming" when the acceptance status can be confirmed. The reference must not imply that a manuscript has been accepted when it has only been submitted or is still under review.

Work that has been submitted but not accepted should not ordinarily be included in the reference list as though it were a published source. When information from an unpublished observation or personal communication is essential and cannot reasonably be obtained from a retrievable source, the authors must identify it accurately in the text and obtain appropriate permission and confirmation of accuracy from the source where required.

Personal communications should not be used merely to avoid locating a publicly available source or to support a major scientific conclusion that requires verifiable evidence. The author should provide sufficient context for the reader to understand the nature of the communication without disclosing confidential information improperly.

Authors must not cite fabricated, inaccessible, or unverifiable material as though it were an established scholarly publication.

Corrected, Retracted, and Disputed Publications

Authors must check the current publication status of references that are important to the manuscript's principal arguments, particularly where the source has a known correction, expression of concern, or retraction.

A retracted article must not be cited as reliable evidence supporting a scientific claim without explicitly addressing its retracted status and the reason it is being discussed. Where the purpose is to describe the retraction, the citation should make the status clear and include the relevant retraction notice where available.

If an article has been corrected, authors should consult the corrected record and ensure that their citation and interpretation reflect the information appropriate to the claim being made.

The existence of a correction or retraction does not automatically make every reference to the original article inappropriate. The relevant consideration is whether the article is being cited accurately and for a purpose consistent with its current status.

Authors are responsible for ensuring that references do not misrepresent the current scientific record. Bibliographic databases and publisher records may assist in verifying publication status, but authors must inspect the relevant source when a material concern arises.

Citation of Artificial Intelligence Outputs

AI-generated content must not be used as a substitute for a verifiable scholarly source when supporting scientific claims. Authors should cite the original research, official document, dataset, or other authoritative source that supports the statement whenever such a source is available.

An AI system's response is not, by itself, evidence that a factual or scientific claim is correct. References suggested by AI tools must be independently verified before inclusion in the reference list, including confirmation that the cited work exists and supports the relevant statement.

Where AI-assisted activities are subject to disclosure requirements, those requirements remain governed by ETFLIN's separate AI policy. This Citation Policy addresses the verifiability and appropriateness of cited sources, rather than the general rules for declaring AI use.

Reference Management Software

Authors may use reference management software to organize references, generate in-text citations, and format the reference list. ETFLIN provides a customized Vancouver style file for Mendeley users to facilitate compliance with its citation format.

Other reference management tools may also be used if the resulting output conforms to the ETFLIN Vancouver style. Authors should inspect the final manuscript after automated formatting, particularly when working with online sources, preprints, datasets, article identifiers, or other reference types that may not be formatted correctly by default templates.

Software-generated bibliographic fields should not be accepted without verification. Incorrect journal abbreviations, missing author names, duplicated references, invalid DOIs, and other formatting or metadata errors remain the responsibility of the authors.

Editorial Assessment and Enforcement

The editorial team may examine references during initial assessment, peer review, revision, and final production. Editorial checks may identify incomplete entries, incorrect citation numbering, inconsistent bibliographic details, sources that cannot be verified, or references that do not appear to support the associated statements.

Authors may be asked to correct, remove, replace, or clarify a citation before the manuscript proceeds. Such requests should be addressed promptly and must not be interpreted as a requirement to add references that are irrelevant to the manuscript.

Where a reference is inaccurate but can be corrected, the editor may request a correction rather than treating every bibliographic error as misconduct. However, fabricated references, intentional misrepresentation of a source, deliberate concealment of the status of a cited article, or systematic manipulation of citation patterns may constitute serious breaches of publication ethics.

Concerns that go beyond ordinary reference-formatting errors may be referred for assessment under ETFLIN's applicable publication ethics procedures. Any editorial action will depend on the nature, extent, intent, and significance of the problem and on the available evidence.

All necessary corrections to references must be completed before the article is finalized for publication. If a material citation error is discovered after publication, ETFLIN will assess whether a correction or another appropriate editorial action is required to preserve the accuracy of the scholarly record.

Policy Review

ETFLIN will periodically review this policy to ensure consistency with its Vancouver citation requirements, developments in scholarly referencing, and recognized publication ethics principles.

The editorial team may update the reference examples or technical formatting requirements when needed to maintain consistency across the journal portfolio. Authors are responsible for using the current version of the policy and checking their references before submission.

Questions concerning citation style or reference formatting may be directed to the relevant journal's editorial office or to halo@etflin.com.