Your professor said "bibliography." Your style guide says "References." The MLA guide says "Works Cited." They are not all the same thing, and getting the name wrong on the page header is exactly the kind of detail that costs you marks for no good reason. Let us sort it out.
Bibliography vs Works Cited vs References: they are not the same
This is the most important thing in this entire guide. These three terms are not interchangeable, even though people (including professors) sometimes use them that way:
References (APA 7th)
Only sources you actually cited in your paper. If you read it but did not cite it, it does not appear here. The title at the top of the page is 'References' in bold.
Works Cited (MLA 9th)
Same rule as APA References: only cited sources. The title at the top is 'Works Cited' (not 'Bibliography', not 'References').
Bibliography (Chicago)
Can include sources you consulted but did not directly cite. This is the broader version. Chicago authors sometimes include background reading that informed their work even without a direct citation in the text.
When a professor says "add a bibliography" without specifying a style, they almost certainly just mean "list your sources at the end." But once you know which style guide you are using, use the correct terminology for that style.
How to format the page itself
Regardless of whether it is called References, Works Cited, or Bibliography, the physical formatting of the page is similar across all three styles:
Start on a new page
The bibliography page is always on a new page at the end of your document, after the main text and any appendices.
Page title
APA: 'References' bold, centered. MLA: 'Works Cited' centered, not bold. Chicago: 'Bibliography' centered.
Double-spaced
All three styles use double-spacing throughout the entire reference list, including between entries. There is no extra blank line between entries.
Hanging indent
All three styles use hanging indent format. First line of each entry flush left, all following lines indented 0.5 inches (1.27 cm).
Alphabetical order
All three styles alphabetize by first author's last name. See below for how to handle tricky cases.
The hanging indent: what it actually is
A hanging indent is the opposite of a regular paragraph indent. In a hanging indent, the first line sits at the left margin, and every line after the first is indented 0.5 inches. Here is a visual:
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus
and Giroux.
Smith, J. A., & Jones, B. (2020). Why students struggle with
citations. Journal of Academic Writing, 5(2), 14–28.
https://doi.org/10.xxxx/example
How to create a hanging indent in common word processors:
Microsoft Word
Select the text, then Ctrl+T (Windows) or Cmd+T (Mac). Or go to Home > Paragraph settings > Indents > Special > Hanging.
Google Docs
Select the text, then Format > Align and indent > Indentation options > Special indent > Hanging > 0.5 inches.
LibreOffice Writer
Select the text, then Format > Paragraph > Indents and Spacing > Before text: 0.5in, First line: -0.5in.
Alphabetical order: the tricky cases
Most entries are simple to alphabetize. But there are a few situations where students consistently get it wrong:
Mac, Mc, and M'
All three prefixes are alphabetized as if they are spelled out fully as "Mac". So McDonald comes before Mackenzie, which comes before MacAlister. Do not alphabetize them as separate M-a-c vs M-c words.
O' prefixes (O'Brien, O'Neill)
Alphabetize as if the apostrophe is not there. O'Brien alphabetizes as OBrien, before O'Neill (ONiell). They fall after any names starting with On- but before Op-.
No author: alphabetize by title
When there is no author, move the source into the alphabetical order based on the first word of the title. Ignore "A", "An", and "The" at the start of a title. So "The Great Gatsby" alphabetizes under G, not T.
Numbers in titles
A title starting with a number is alphabetized as if the number is spelled out. "1984" alphabetizes under N (nineteen eighty-four). "50 Ways" alphabetizes under F (fifty ways).
Multiple works by the same author
When you have cited two or more works by the same author, how you order and format them depends on the style:
APA 7TH: SAME AUTHOR
Kahneman, D. (1973). Attention and effort. Prentice Hall.
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.
Order by year, earliest first. Repeat the author name on each entry.
CHICAGO: SAME AUTHOR (3-EM DASH)
Kahneman, Daniel. Attention and Effort. Prentice Hall, 1973.
———. Thinking, Fast and Slow. Farrar, Straus and Giroux, 2011.
Use 3-em dash in place of the repeated author name on entries after the first.
Common bibliography mistakes
Mistake: Including sources not cited in the text
Fix: In APA and MLA, every source in your reference list must have a corresponding in-text citation. If you read something but did not cite it, leave it out (unless Chicago style).
Mistake: Missing sources that were cited
Fix: Every in-text citation must have a matching reference list entry. Go through every (Author, Year) or (Author page) in your paper and verify each one has a full entry.
Mistake: Wrong order within same-author entries
Fix: APA orders same-author works from earliest to latest year. Two works by the same author in the same year get a, b, c suffixes: (2021a) and (2021b).
Mistake: Inconsistent capitalization
Fix: APA uses sentence case for article and book titles (only first word and proper nouns capitalized). MLA and Chicago use title case (most words capitalized). Pick one and be consistent throughout.
Mistake: Period after the URL or DOI
Fix: Do not put a period at the end of a URL or DOI. The period makes it look like part of the link. The citation just ends with the URL, no punctuation.
Mistake: Forgetting the hanging indent
Fix: Set your word processor to hanging indent before you start pasting citations. It is much harder to add afterward when you have a full list.
What is an annotated bibliography?
An annotated bibliography is a bibliography where each entry is followed by a short paragraph (the annotation) that summarizes the source and evaluates its relevance or quality. Some professors assign these as part of the research process.
EXAMPLE ANNOTATED BIBLIOGRAPHY ENTRY (APA)
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.
This book provides an accessible account of Kahneman's dual-process theory of cognition, distinguishing between fast intuitive System 1 thinking and slower deliberate System 2 thinking. The writing is accessible without sacrificing accuracy, making it suitable for an undergraduate audience. Particularly useful for the section on cognitive biases and their effect on financial decision-making.
Annotations are typically 100 to 200 words per entry. The format of the citation itself is the same as a regular bibliography — the annotation just follows underneath, indented.
A complete mini-example: APA reference list
Here is what a properly formatted APA reference list looks like with four different source types:
References
Baumeister, R. F., Bratslavsky, E., Finkenauer, C., & Vohs, K. D. (2001). Bad is stronger than good.
Review of General Psychology, 5(4), 323–370. https://doi.org/10.1037/1089-2680.5.4.323
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.
National Institutes of Health. (2023, October 3). Mental health and the workplace.
https://www.nih.gov/mental-health-workplace
Sinek, S. [TED]. (2010, September 28). How great leaders inspire action [Video]. YouTube.
https://www.youtube.com/watch?v=qp0HIF3SfI4
Save time: use FreeCitation to build your list
FreeCitation lets you generate individual citations for websites, journal articles, books, and YouTube videos, then saves them all in a list you can export. It handles the hanging indent formatting, alphabetical order, and style-specific rules automatically. You focus on your paper, not the punctuation.
Frequently asked questions
Can I have a bibliography AND a works cited page?
Only if your assignment specifically asks for both, which is unusual. Normally you have one list at the end. The name of that list depends on your citation style. If you are in APA, it is 'References.' If you are in MLA, it is 'Works Cited.' If you are in Chicago, it is 'Bibliography.' Pick one and stick with it.
What if my source has no author AND no title?
This is extremely rare for academic sources. If you genuinely cannot identify an author or a usable title, reconsider whether this source is worth citing — it might not be a credible or verifiable source. If you must include it, use a description of the content in square brackets where the title would go: [Description of content]. Then alphabetize by that description.
How many sources should a bibliography have?
There is no fixed rule and it varies enormously by assignment. A 2,000-word undergraduate essay might have 10 to 15 sources. A 10,000-word dissertation chapter might have 40 or more. Your professor may have specified a minimum number of sources — if so, check the assignment brief. The goal is to support every substantive claim in your paper, not to pad the list with sources you barely used.
Related guides: DOI vs ISBN, citing YouTube videos, citing websites in APA, and OSCOLA for law students.