Citations are references to sources of information used in academic writing to give credit to the original authors and provide evidence for claims or arguments. A citation style is a standardized set of guidelines for referencing sources in academic publications. They dictate the information necessary for a citation such as how to format in-text citations, footnotes or endnotes, and reference lists or bibliographies. Different academic disciplines and publications follow different citation styles, each with its unique conventions for citing books, articles, websites, and other sources. Adhering to a citation style and format is essential to maintain consistency, clarity, and accuracy in scholarly writing.
In general, there are three basic types of citation styles: parenthetical, numerical, or note citations.
Parenthetical citation style:
Parenthetical citation style uses parentheses to enclose the author’s last name and the publication year, separated by a comma. This style seamlessly integrates with the narrative, allowing the reader to identify the source quickly and is commonly used in APA, MLA, and Harvard citation formats.
Parenthetical citation Example
APA and Harvard Style:
- Author’s last name and the publication date is included in parentheses, e.g., (Smith, 2020).
- For a quote from the source, page number is included, e.g., (Smith, 2020, p. 45).
- If the author’s name is mentioned in the text, only the date is enclosed in parentheses, e.g., “According to Smith (2020),…”
- When author name and date is known: e.g., (Smith, 2020); (Johnson & Brown, 2019)
- When author name and date is NOT known: Other identifying information such as the title of the webpage is used, e.g.,(“webpage title” n.d.)
- Author’s last name and the page number is enclosed in parenthesis, e.g., (Jones 45).
- If the author’s name is mentioned in the text, only the page number is enclosed in parentheses, e.g., “Jones argues that (45)…”
Notes-bibliography style: In-text citations are indicated with superscript numbers that correspond to the full citation in the footnote or endnote; e.g., Their study findings were interesting.1
Author-date style: Author’s last name and publication date is included within parentheses in the text, Recent research has explored this topic (Author Last Name Year, page number).
Numerical Citation style:
Numerical citations are widely used in scientific research papers, where numerous sources are cited and allows readers to locate and cross-reference sources efficiently. In this format, each source is assigned a number, often presented in square brackets or superscript within the text, which corresponds to a full citation in a numbered list at the end of the document.
Numerical Citation Example:
“Cystatin C is a non-glycosylated protein produced by all nucleated cells .
Corresponding reference entry: “1. Griffin BR, Faubel S, Edelstein CL. Biomarkers of drug-induced kidney toxicity. Ther Drug Monit 2019;41:213-26.”
Note Citation style:
Note citations, also known as footnotes and endnotes, are used to reference sources, provide explanatory notes, or make comments without disrupting the flow of the main text. Note citations can be found either at the bottom of each page (footnotes) or at the end of the document (endnotes). Both types are sequentially numbered and contain comprehensive source details, facilitating easy source verification for readers. Examples of footnote citations in Chicago style are:
- Notes-bibliography style:
“Examples of fullnotes1 and short notes2”
1. Bergers, Gabriele and Benjamin, Laura. Tumorigenesis and the angiogenic switch. Nat Rev Cancer 2003;3:401-10.
2. Bergers and Benjamin. Tumorigenesis and angiogenic switch, 401-10.
- Author-date style:
“The important role of angiogenesis in tumor development and progression is well known (Bergers and Benjamin 2003, 401).”