CASRAI Dictionary

Tag: reference list

  • In-Text Citations vs Reference List Explained

    An in-text citation is the brief marker placed in the body of a document at the exact point where a source is used; the reference list is the full set of entries at the end that the markers point to. A citation system is the disciplined pairing of these two halves — a short signal in the text and a complete record at the back — so that any reader can move from a claim to its source and back again.

    The two halves are designed for different jobs. The in-text marker is kept minimal so it does not disrupt reading. The reference entry is kept complete so retrieval never fails. Neither works alone: a marker with no entry is a dead end, and an entry with no marker is an orphan.

    The two halves of a citation system

    Every mainstream citation system is built from the same pairing, even though the surface format differs:

    • In-text citation — an author–date marker such as (Okafor, 2020) or a numeric marker such as [7], sitting beside the borrowed material.
    • Reference list entry — the full bibliographic record, carrying author, year, title, container and a persistent identifier so the source can be located.

    This is the structural backbone described in our explainer on what a citation is.

    Author–date systems

    Author–date systems — used by APA and the author–date variant of Chicago — place the author surname and year of publication in the text. The reader matches that surname to the alphabetised reference list. A page number is added for direct quotations.

    For example, an in-text marker of (Okafor, 2020, p. 14) maps to a reference list entry beginning Okafor, A. (2020). Because the list is alphabetised, the reader scans to “O” and finds the full record. The strength of this system is that the reader sees author and date without leaving the sentence, which signals currency and authority inline.

    Numeric systems

    Numeric systems — Vancouver, used across medicine and many sciences under ICMJE conventions — replace the author–date marker with a number assigned in order of first appearance. The reference list is ordered numerically to match. An in-text marker of [7] sends the reader to the seventh entry in the list.

    Numeric markers keep the running text uncluttered, which suits papers with very many references. The trade-off is that the reader cannot tell who or when from the marker alone — they must turn to the list.

    Worked example: the same source, two systems

    System In-text marker Reference list entry (schematic)
    APA 7 (author–date) (Okafor, 2020) Okafor, A. (2020). Title of work. Publisher. https://doi.org/…
    Vancouver (numeric) [1] 1. Okafor A. Title of work. Publisher; 2020. Available from: https://doi.org/…

    Note how the data elements — author, year, title, publisher, DOI — are identical; only the order, punctuation and the form of the in-text marker change. That stability of elements beneath varying surface format is the central insight of comparing citation styles.

    How markers map to entries

    The integrity of a citation system depends on a clean one-to-one mapping. Every in-text marker must have exactly one matching reference entry, and — in a reference list, as opposed to a fuller bibliography — every entry must correspond to at least one in-text marker.

    • No orphan entries. A reference with no in-text marker suggests background reading that belongs in a bibliography, not a reference list.
    • No dangling markers. An in-text citation with no matching entry leaves the reader unable to retrieve the source.
    • Consistent identifiers. Author names should be disambiguated — an ORCID iD resolves the “which J. Smith?” problem — and persistent identifiers such as DOIs should resolve.

    Maintaining this mapping is also a matter of research integrity: a broken link between marker and entry undermines the verifiability that citation exists to provide.

    Choosing and applying a system

    Discipline usually dictates the choice: author–date for the social sciences and humanities, numeric for medicine and many natural sciences. Whatever the system, the rule is consistency — apply one set of conventions throughout, and let a reference manager enforce the marker-to-entry mapping for you. Practical guidance for getting this right lives in our resources for authors.

    Frequently asked questions

    What is the difference between an in-text citation and a reference?

    An in-text citation is the brief marker in the body of the text. A reference is the full entry in the reference list that the marker points to. They are two halves of one citation: the marker signals where a source is used, and the entry lets the reader retrieve it.

    How do numeric and author–date systems differ?

    Author–date systems put the author surname and year in the text and alphabetise the reference list. Numeric systems use a number assigned in order of first appearance and order the list to match. Numeric markers are more compact; author–date markers show authorship and currency inline.

    Should every reference list entry have an in-text citation?

    Yes, in a reference list. A reference list contains only sources actually cited, so every entry should map to at least one in-text marker. Background reading that was not cited belongs in a bibliography instead.

    Where can I check standardised definitions of these terms?

    The CASRAI dictionary provides standardised definitions, and our comparison of citation styles shows how different systems format the same source.

  • APA Reference List Format: Worked Examples

    An APA reference list is the alphabetically ordered set of full source entries placed at the end of a document, each formatted with a hanging indent and corresponding to an in-text citation. It follows the author–date conventions of the Publication Manual of the American Psychological Association (7th edition). Every work cited in the text appears once in the list, and every entry in the list is cited at least once in the text — the two must match exactly.

    The reference list is where APA’s four-element logic — author, date, title, source — becomes a precise, repeatable format. If you are new to the author–date system, start with our APA 7th edition essentials before building a full list.

    The three formatting rules that govern every entry

    Three mechanical rules apply to the whole list. First, alphabetical order by the first author’s surname; works by the same author are then ordered by year, earliest first. Second, a hanging indent: the first line of each entry sits at the left margin and every subsequent line is indented, so surnames are easy to scan. Third, the list is double-spaced with no extra blank lines between entries, and titled “References”, centred and bold, on a new page.

    Worked examples by source type

    The table below shows a correctly formatted entry for each major source type. Author names and years are illustrative placeholders, but the punctuation, italics and ordering are exactly as APA 7 requires.

    Source type Worked example
    Journal article Smith, J. A. (2021). Open-access uptake in clinical trials. Journal of Research Standards, 14(3), 220–238. https://doi.org/10.1000/jrs.2021.0143
    Book Brown, T. R. (2019). Foundations of research integrity. Academic Press.
    Chapter in an edited book Lee, S. (2020). Data-sharing norms. In R. Patel (Ed.), Open science in practice (pp. 45–67). University Press.
    Website / web page Jones, R. B. (2022, March 4). Metadata standards for research outputs. Research Standards Institute. https://example.org/metadata-standards
    Dataset Patel, A., & Khan, M. (2021). Citation-coverage survey 2021 [Data set]. Open Data Repository. https://doi.org/10.1000/odr.2021.0099

    Reading the journal-article entry

    Take the journal example apart. The author block inverts the name and uses initials. The year sits in brackets. The article title is in sentence case and not italicised — only the first word and proper nouns are capitalised. The journal name and volume number are italicised; the issue number, in brackets, is not. The page range and DOI close the entry, with no full stop after the DOI. This single pattern, with small variations, drives most of the references you will ever write.

    Handling books, chapters and the publisher rule

    Books reverse the italics: now the title is italicised in sentence case, and the publisher closes the entry. APA 7 dropped the publisher’s city, so “Academic Press” stands alone. For a chapter, you cite the chapter author and chapter title first, then “In”, the editor(s) with initials before the surname, the italicised book title, the page range in brackets, and the publisher. Knowing exactly who is credited at chapter versus volume level matters for fair attribution of credit.

    Websites, datasets and DOI formatting

    Web pages need a specific date where available — year, month and day — and the name of the hosting organisation as the “source”. Datasets are cited as first-class outputs: author, year, italicised title, a bracketed format description such as [Data set], the repository name and a DOI. Treating data this way reflects the modern research-outputs landscape, where datasets, software and protocols are citable on their own terms.

    For DOIs, always use the full https://doi.org/ form, with no trailing punctuation. If an online source has no DOI but has a stable URL, give the URL; if the content is likely to change, add a retrieval date. A persistent identifier is what links your entry to the durable scholarly record.

    Ordering edge cases

    Two situations trip people up. When one author has several works in the same year, distinguish them with lowercase letters on the year — (2021a), (2021b) — ordered by title, and mirror those letters in the in-text citations. When alphabetising, treat “nothing before something”: Smith, J. comes before Smith, J. A. Single-author entries precede multi-author entries that begin with the same surname.

    Frequently asked questions

    Should every cited source appear in the reference list?

    Yes — with one exception. Standard in-text-only items such as personal communications (emails, interviews not recoverable by a reader) are cited in the text but not listed, because there is nothing the reader can retrieve. Everything recoverable must appear.

    How do I order two works by the same author?

    By year, earliest first. If the years are identical, add lowercase letters to the year and order alphabetically by title. Single-author works always come before that author’s collaborative works.

    Do I keep the hanging indent in a numbered or bulleted list?

    The reference list is never numbered or bulleted in APA. It is a plain, double-spaced list with a hanging indent on each entry. Numbered referencing belongs to other styles, such as Vancouver.

    Where can I confirm an unusual entry?

    For conference papers, theses, software or grey literature, check your institution’s APA guide or the Publication Manual. CASRAI’s author guidance and standards dictionary can help you decide how to describe an output before you format it.

  • What Is a Bibliography? Definition, Types and How to Compile

    A bibliography is an organised, alphabetised list of sources relevant to a piece of scholarly work, placed at the end of a document. Depending on the convention in use, a bibliography may list only the sources cited or may also include background works consulted but not directly cited. Its purpose is to record the intellectual context of a work and let readers locate every source behind it.

    The word carries more than one meaning in scholarship. In some citation systems “bibliography” is the standard name for the end-of-document source list; in others it is distinguished sharply from a reference list. Understanding which sense applies is the first step to compiling one correctly.

    Bibliography versus reference list

    The clearest way to grasp a bibliography is to set it against the reference list it is often confused with.

    Feature Reference list Bibliography
    Contents Only sources cited in the text May include cited and uncited background reading
    Mapping to text One-to-one with in-text citations Need not map to every in-text marker
    Typical styles APA, Vancouver (as “References”) Chicago notes-bibliography, MLA (“Works Cited”)

    A reference list answers the question “what did you cite?” A bibliography can answer the broader question “what shaped this work?” The mapping between in-text markers and entries is covered in in-text citations versus the reference list.

    Types of bibliography

    Enumerative bibliography

    The most common form: a straightforward list of sources, alphabetised by author surname, each entry formatted to a chosen style. This is what most students and researchers mean by “a bibliography”.

    Annotated bibliography

    Each entry is followed by a short paragraph — the annotation — that summarises the source, evaluates its relevance or quality, and notes how it relates to the project. Annotated bibliographies are common in literature reviews and proposals, where the reader benefits from the author’s assessment of each source.

    Analytical and descriptive bibliography

    A specialist scholarly field concerned with books as physical objects — their printing, editions and material history. This sense is distinct from the everyday end-of-paper list and belongs to textual scholarship rather than routine citation.

    How to compile a bibliography

    Compiling a reliable bibliography is a disciplined, repeatable process.

    • Record sources as you read. Capture full bibliographic detail — author, year, title, container, publisher and a persistent identifier such as a DOI — at the moment you consult each source, not afterwards from memory.
    • Choose one citation style and apply it consistently. The required elements are stable, but their order and punctuation are not. See citation styles compared to select the right one.
    • Decide cited-only or cited-plus-background. Confirm whether your style and assignment want a reference list or a fuller bibliography, then include sources accordingly.
    • Alphabetise and format. Order entries by the first author’s surname and apply a hanging indent so each entry is easy to scan.
    • Verify every entry. Check that each persistent identifier resolves and that names are disambiguated — an ORCID iD helps distinguish authors with similar names.

    How to order and format entries

    Most enumerative bibliographies are ordered alphabetically by the lead author’s surname. Where an author has several works, they are usually ordered by year. Numeric systems such as Vancouver are an exception: there the list is ordered by the sequence of first appearance in the text, not alphabetically. Each entry typically uses a hanging indent, and titles, journals and books are styled per the chosen system.

    System Ordering principle
    Author–date (APA, Chicago author–date) Alphabetical by surname, then by year
    MLA Works Cited Alphabetical by first listed name or title
    Numeric (Vancouver) By order of citation in the text

    Relationship to works cited and references

    “Works Cited” is MLA’s name for its end-of-paper list and contains only cited sources, making it functionally a reference list rather than a full bibliography. Knowing the vocabulary your discipline uses prevents the common error of mixing background reading into a list that should be cited-only. Sound bibliographies also support research integrity, because a complete, accurate source list lets others verify and build on your work.

    Frequently asked questions

    Is a bibliography the same as a reference list?

    Not always. A reference list contains only the sources you cited. A bibliography may also include background works you read but did not cite. Some styles, however, use “bibliography” as the name for what others call a reference list, so always check your style’s convention.

    What is an annotated bibliography?

    An annotated bibliography adds a short evaluative paragraph after each entry, summarising the source and explaining its relevance. It is common in literature reviews and research proposals where readers benefit from the author’s assessment of each work.

    How do I order a bibliography?

    Most bibliographies are alphabetised by the lead author’s surname, then by year for multiple works by the same author. Numeric systems such as Vancouver are the exception and order entries by their first appearance in the text.

    Where can I find standardised definitions of these terms?

    Consult the CASRAI dictionary for standardised definitions, and our explainer on what a citation is for how individual references fit together.

  • IEEE and AMA Citation Styles Explained

    IEEE citation uses bracketed numbers in the text that point to a numbered reference list, and is standard across engineering and computer science. AMA citation, used widely in medicine, uses superscript numbers instead. Both are numeric systems, but they differ in formatting, ordering and discipline.

    This guide explains how each style handles in-text markers and reference entries, with worked examples and a side-by-side table.

    IEEE: numbers in square brackets

    In IEEE style, each source is assigned a number the first time it is cited, in square brackets, and that number is reused for every later citation of the same source. References are listed in the order they first appear — not alphabetically.

    • In-text: Recent work on neural search has improved recall [1], and later studies confirmed it [2], [3].
    • Reused number: The original architecture [1] remains the baseline.
    • As a noun: As shown in [4], latency dropped sharply.

    A reference-list entry abbreviates author first initials and places the number in brackets:

    [1] J. Smith and A. Jones, “A scalable indexing method,” IEEE Trans. Knowl. Data Eng., vol. 33, no. 4, pp. 110–128, 2021.

    AMA: superscript numbers

    AMA style places superscript numerals after the relevant text, again numbered in order of first appearance. The reference list follows the same numeric order. AMA dominates clinical and biomedical journals.

    • In-text: Adherence improved across the cohort.1
    • Multiple sources: Several trials reported the same effect.2,3
    • Range: The pattern held across studies.4-6

    A reference entry uses journal abbreviations and a specific punctuation pattern:

    1. Smith J, Jones A. Outcomes in the treatment cohort. J Clin Res. 2021;12(3):110-128.

    IEEE versus AMA at a glance

    Feature IEEE AMA
    Discipline Engineering, computer science Medicine, biomedicine
    In-text marker Square brackets [1] Superscript 1
    List order Order of appearance Order of appearance
    Author names Initials before surname: J. Smith Surname then initials: Smith J
    Title style Article title in quotes Article title, no quotes
    Journal name Abbreviated, italic Abbreviated, italic

    Why discipline drives style choice

    Numeric styles keep the running text uncluttered, which suits dense technical and clinical writing where a single sentence may lean on several sources. IEEE’s bracketed numbers double as compact cross-references to equations, figures and prior work; AMA’s superscripts keep medical prose readable at speed. Compare this with author-date approaches in our guide to Harvard referencing, where the author’s name carries into the sentence.

    For a wider map of the field, see citation styles compared, and for general technique, our practitioner guide to citing sources.

    Common pitfalls

    The most frequent IEEE error is alphabetising the reference list — it must follow first-appearance order. The most frequent AMA error is mixing in author-date phrasing (“Smith showed¹”) inconsistently; keep the superscript doing the work. In both styles, every number in the list must be cited at least once in the text, and vice versa. Our for authors guidance covers reference hygiene before submission.

    How citation style fits research outputs metadata

    Citation style governs the visible reference; controlled vocabulary in our dictionary and contributor attribution through CRediT govern the structured metadata around it. Together they make a paper’s outputs machine-readable. Explore more in research outputs.

    Frequently asked questions

    Are IEEE and Vancouver the same?

    They are close cousins — both numeric, both ordered by appearance — but differ in formatting detail, and Vancouver is associated with biomedicine while IEEE is associated with engineering. AMA is itself a Vancouver-derived medical style.

    Do IEEE numbers go inside or outside punctuation?

    IEEE brackets typically sit before the full stop, treated as part of the sentence: “…confirmed the result [2].”

    Can I cite the same AMA source twice?

    Yes — reuse its original number every time it appears, just as in IEEE.

    Which style should a computer science thesis use?

    IEEE is the conventional default for computer science and electrical engineering, but always follow your department’s or publisher’s stated requirement.

  • Harvard Referencing Style: A Complete Guide

    Harvard referencing is an author-date citation system in which sources are cited in the text by the author’s surname and the year of publication, with full details listed alphabetically in a reference list. There is no single governing body for Harvard, so exact punctuation varies between universities; consistency within one document matters more than any universal rule.

    This guide covers the in-text format, the reference-list format, the major institutional variants and worked examples you can adapt.

    Why there is no single “Harvard” authority

    Unlike APA, which is maintained by the American Psychological Association, Harvard is a family of author-date styles rather than a centrally published standard. Many institutions publish their own Harvard guide, and the British Standard BS ISO 690 informs several of them. The practical consequence: punctuation, italicisation and the use of “and” versus “&” differ between guides. Always follow the specific guide your department or journal mandates, and apply it uniformly.

    For a wider comparison of conventions across the citation landscape, see our overview of citation styles compared.

    In-text citations: (author, year)

    Harvard in-text citations name the author and year in parentheses, adding a page number for direct quotations.

    • Paraphrase: Research participation rose sharply over the decade (Smith, 2021).
    • Direct quote: The findings were “unambiguous and replicable” (Smith, 2021, p. 14).
    • Author named in sentence: Smith (2021) argued that the trend was structural.
    • Two authors: (Smith and Jones, 2020) — some variants use an ampersand: (Smith & Jones, 2020).
    • Three or more: (Smith et al., 2019).

    Where an author has several works in the same year, distinguish them with letters: (Smith, 2021a), (Smith, 2021b).

    The reference list

    The reference list appears at the end, ordered alphabetically by author surname. A typical journal-article entry reads:

    Smith, J. (2021) ‘Patterns of research participation’, Journal of Research Methods, 12(3), pp. 110–128.

    A book entry:

    Jones, A. (2020) Designing the Research Question. 2nd edn. London: Academic Press.

    Core elements are author, year, title, source and locator. Italicise the title of the standalone work (the journal or the book), and place the article title in quotation marks where the variant requires it.

    Institutional variants you will meet

    Because Harvard is decentralised, you will encounter small but stubborn differences. The table below illustrates a few common points of divergence; treat them as examples, not as ranked authorities.

    Feature Variant style A Variant style B
    Two-author connector Smith and Jones Smith & Jones
    Year placement Smith, J. (2021) Smith, J., 2021.
    Article title ‘In quotes’ No quotes, sentence case
    Page abbreviation pp. 110–128 110–128

    The recurring lesson is the same one we stress in our for authors guidance: choose one variant, document it, and apply it without exception.

    Citing electronic sources in Harvard

    Web pages take the same author-date logic with an access date added, because online content can change. For a full walkthrough across styles, see our companion piece on how to cite a website correctly. For numeric and superscript alternatives used in engineering and medicine, see IEEE and AMA citation styles explained.

    How Harvard fits the wider research output

    Referencing is one strand of describing scholarship clearly. Controlled terminology in our dictionary and contributor roles via CRediT complement consistent citation by making the rest of a paper’s metadata as unambiguous as its reference list. Browse more in research outputs.

    Frequently asked questions

    Is Harvard the same as APA?

    No. Both are author-date systems, but APA is a single published standard with fixed rules, whereas Harvard is a family of similar styles with institution-specific punctuation. Our APA essentials guide details the APA-specific conventions.

    Which Harvard variant should I use?

    The one your department, publisher or journal specifies. If none is mandated, pick a reputable institutional guide and follow it consistently throughout the document.

    Do I need page numbers for paraphrases?

    Page numbers are required for direct quotations and recommended when pointing to a specific passage. For general paraphrase of a whole source, author and year usually suffice.

    How do I cite a source with no author?

    Use the title in place of the author, or the organisation responsible. Practical strategies for missing metadata appear in our practitioner guide to citing sources.