Citation styles compared: Harvard, Vancouver, Chicago, MLA

Which citation style should you use?

Mostly the choice is not yours. In a thesis, the university’s thesis guidelines or your department fix the style. Some Indian universities give one style for all subjects. Some leave it to each department. Many only write “a standard style, used consistently”. For a journal paper you have to follow the author guidelines of that journal, and many journals change a standard style slightly for their own use.

If the thesis rules don’t name any style, take the style most common in the journals you read. Examiners from your field will already know it. One reference library then serves papers and thesis both. If your university asks, name the style in the front matter or methodology. Then use that one style only in every chapter.

How do the styles compare side by side?

The tables below use one real article, the 2006 paper by Braun and Clarke on thematic analysis, so every style shows the same source. Page 79 is the example quotation page.

See what changes. Harvard, APA and Vancouver put the initials after the surname. Chicago and MLA write full first names, and IEEE puts the initials first. Chicago and MLA give the article title in title case, the other four in sentence case. Quotation marks and journal abbreviations also change from style to style. A scholar may feel these are small things, but a reference list with a bit of each habit gets caught by the examiner on the first page itself.

Harvard and Vancouver: what to watch for

Harvard

When people say “Harvard”, they mean a whole family of author-date styles. Nobody publishes a Harvard manual. Each university and each publisher has made its own version. One version writes “p.” before the page and another drops it. Punctuation, the number of authors before “et al.” and online sources also vary. Most scholars mean Cite Them Right, published in the UK and used by many universities there. Your university guidelines may give a Harvard example. In that case copy that example exactly, even if it is different from Cite Them Right.

Scholars go wrong at two places. The first is that Harvard and APA look very similar, so many theses end up as a mix of both. One citation has “and” and the next one has “&”. Chapter 2 has “p. 79” and chapter 4 has just “79”. Decide your form and search the full thesis for the other one. The second place is the year in the reference list. Most Harvard versions put the year in round brackets just after the authors, and no full stop comes after it. APA puts a full stop there. The Harvard form is “(2006) ‘Using…’” and the APA form is “(2006). Using…”.

Vancouver

Most medical and health science journals use Vancouver, which is a numbered style. It comes from the ICMJE recommendations and from Citing Medicine of the National Library of Medicine. Each source gets a number in the order you cite it for the first time. The reference list also goes in that same order and not alphabetically.

• Numbers in the text can be in square brackets, round brackets or superscript. See what your target journal wants and keep one form throughout.
• Author names are surname plus initials with no full stops or spaces, as in “Braun V, Clarke V”. In many journals you list first six authors and then put “et al.”
• Journal titles are shortened in NLM form, for example “Qual Res Psychol”. If NLM indexes the journal, search it in the NLM Catalog and copy the official abbreviation.
• Punctuation is sparse, so year, volume, issue and pages are run together as 2006;3(2):77-101.

Chicago and MLA: what to watch for

Chicago has two systems

The Chicago Manual of Style has two separate systems, and a thesis picks one of them and stays with it till the end.

Author-date is similar to Harvard or APA. In the text you write (Braun and Clarke 2006, 79). Look carefully, no comma after “Clarke” and no “p.” before 79. The reference list puts the year right after the authors.

Notes and bibliography is the older system that humanities subjects use. In the text you put a superscript number, and that number leads to a footnote or an endnote. The first note for a source gives full informations about it. Later notes use a short form. See the two notes below.

• First note: 1. Virginia Braun and Victoria Clarke, “Using Thematic Analysis in Psychology,” Qualitative Research in Psychology 3, no. 2 (2006): 79, https://doi.org/10.1191/1478088706qp063oa.
• Later note: 4. Braun and Clarke, “Using Thematic Analysis,” 82.

Chicago now prefers these short notes in place of “ibid.”. At the end there is a bibliography listing the sources alphabetically. A few universities skip the bibliography when the notes are complete, and your guidelines will say. In Word, use Word’s own footnote option. If you type the superscript numbers yourself, one new note in chapter 3 will spoil all the numbers after it.

MLA

MLA was made for literature and language studies. There the page you discuss counts more than the year. So the in-text citation is author and page, without any comma, as in (Braun and Clarke 79). If the sentence already says “Braun and Clarke argue that…”, the bracket carries only (79). MLA calls the reference list “Works Cited”.

In MLA 9 every entry is made up of “core elements” which come in a fixed order. The order is author, title of source, title of container (the journal or book), other contributors, version, number, publisher, date, and location (pages, DOI or URL). Odd sources confuse scholars, but once you get MLA’s container idea they stop troubling you. A poem printed inside an anthology has a container, and so does an episode on a streaming service. For three or more authors, MLA gives the first author and “et al.”, in the text and in Works Cited both.

If you quote a primary literary text again and again, MLA allows short titles and line or chapter numbers in place of page numbers. For editions of classic texts your guide may follow some custom of the department. Go with that custom, and mention the edition one time.

APA 7 and IEEE in brief

APA 7 is an author-date style. Psychology, education, management and many social sciences use it. The in-text form is (Braun & Clarke, 2006), and “et al.” starts from three authors. In the reference list authors go A to Z by surname, with the year in brackets after them. The article title is in sentence case and the DOI is a full https link. APA also has thesis rules for headings, tables and figures, and our APA 7 guide covers them with a reference example for each source type.

IEEE is the numbered style for engineering and computer science. Whichever source you cite first in the text becomes [1], the next new one becomes [2], and the reference list at the end follows the same numbering. Author names come as initials and then surname. For journal titles, IEEE has its own list of short forms. Conference papers, standards, patents and equations are all covered in our IEEE guide.

How do you switch from one citation style to another?

Many scholars think one style will do for the whole PhD, but a change comes up somewhere. Say an IEEE journal rejects your paper and you send it to Elsevier journal which has its own numbered style. Or you wrote a thesis chapter in APA, and now the university format asks for Harvard.

When the citations were put in through a reference manager, the switch is fast. Open Zotero or Mendeley, pick the new style from the style list and refresh. Both of them work with Citation Style Language (CSL) files. Styles exist for most journals and many universities. Setting this up is explained in our Zotero vs Mendeley guide.

If you typed the citations by hand in Word, you have two ways in front of you. One is to rebuild them inside a reference manager. For a thesis this takes a day or two, and the time is well spent. The other is careful conversion by hand. With 200 or more references, rebuilding is almost always faster and safer.

Rebuilt or hand-converted, the new list needs one slow reading before it goes out. A reference manager only formats what is in its database, and that data many times has errors. Mostly it is a title in all capitals or a missing issue number. Sometimes a conference paper got saved as a journal article. After the switch, go down the checks below.

• Check every in-text citation in the new format, mainly the hand-typed ones, because the software never touches them.
• With a numbered style, numbering follows the first citation, so Sharma (2020) keeps its chapter 1 number when it comes back in chapter 5.
• In author-date styles the list is in alphabetical order. When one author has two works in the same year, mark them 2021a and 2021b.
• Reword “as shown in [4]” if you moved to author-date, and “Sharma (2020) found” if you moved to numbers.
• Journal names get shortened when you go to Vancouver or IEEE, and written fully again for Harvard, APA, Chicago or MLA.
• DOIs are in your style’s format, and no DOI is broken across lines in a way that changes it.
• Where your university’s thesis rules differ from the published style, apply them last.

A source cited in the wrong format is only a formatting mistake, and the examiner will ask you to do the corrections. Using somebody’s work without citing it is an academic integrity problem, much more serious. When a citation is needed at all is covered in our paraphrasing guide.