How to Write a Citation: Complete Guide for APA, MLA, Chicago

Look, I get it. Citations feel like that annoying paperwork you do after the real work is finished. You've just written an amazing research paper or article, and now you have to deal with periods, commas, and italics? Seriously? But here's the thing my college professor drilled into me during that brutal sophomore year: mess up your citations, and your brilliant work loses credibility faster than a viral tweet with no sources.

Remember when I cited a YouTube video as "that funny cat tutorial" in my first college paper? Yeah. Professor Williams circled it in red with "???" written so hard it tore the paper. That's when I realized I needed to properly learn how to write a citation.

Why Bother Learning Proper Citation?

Citations aren't just academic busywork. Think of them as giving GPS coordinates for your information. Ever followed a recipe link that just said "add some spices"? Useless. Similarly, citations:

Stop you from accidentally stealing others' work (called plagiarism - which can get you fired or expelled)
Let readers verify your sources, because trust is built on proof, not vibes
Show you understand the conversation happening in your field
Give proper credit where it's due, which is just basic decency

Honestly, I still find Chicago style a bit fussy with all its commas, but doing it right saves headaches later.

Meet the Big Three Citation Styles

Citation styles feel like rival sports teams - each has die-hard fans. Knowing which to use depends entirely on your playground:

Style	Common Fields	Key Features	Annoying Quirk
APA (American Psychological Association)	Psychology, Education, Social Sciences	Date-focused, author-date in-text citations	Requires "Retrieved from" for URLs
MLA (Modern Language Association)	Literature, Arts, Humanities	Author-page in-text, minimal publisher info	Container system confuses everyone
Chicago (University of Chicago Press)	History, Business, Fine Arts	Two systems: notes-bibliography OR author-date	Footnotes. So. Many. Footnotes.

Pro tip: Always ask your instructor or editor which style to use. Don't assume - I wasted 3 hours reformatting a paper once because the department switched from MLA to APA mid-semester.

Wait, What About AMA or IEEE?

Good catch. Medical folks use AMA (American Medical Association), engineers swear by IEEE. But unless you're in those fields, you'll usually stick with the big three when learning how to write a citation.

Your Step-by-Step Citation Cheat Sheet

Ready for the practical stuff? Let's break down how to write a citation for common sources. I'll show real examples so you're not left guessing.

How to Cite Books Like a Pro

Books are the bread and butter of research. Here's the universal formula:

Author Last, First. Book Title in Italics. Publisher, Year.

MLA: Atwood, Margaret. The Handmaid's Tale. McClelland and Stewart, 1985.
APA: Atwood, M. (1985). The handmaid's tale. McClelland and Stewart.
Chicago: Atwood, Margaret. 1985. The Handmaid's Tale. Toronto: McClelland and Stewart.

Got multiple authors? APA uses & before last author, MLA/Chicago use "and":

Style	2 Authors	3+ Authors
APA	Smith, J., & Jones, R.	Smith, J., Jones, R., et al.
MLA	Smith, John, and Rita Jones	Smith, John, et al.

Journal Articles - Where Details Matter

Articles trip people up with volume/issue numbers. Watch closely:

Author. "Article Title." Journal Title, vol., no., Year, pages.

APA: Lee, C. (2023). Citation errors in digital scholarship. Journal of Academic Integrity, 12(3), 45–67. https://doi.org/10.1234/jai.2023.123
MLA: Lee, Chen. "Citation Errors in Digital Scholarship." Journal of Academic Integrity, vol. 12, no. 3, 2023, pp. 45–67.
Chicago: Lee, Chen. 2023. "Citation Errors in Digital Scholarship." Journal of Academic Integrity 12 (3): 45–67.

Warning: Forget the italics for journal titles and I will find you. Just kidding. But seriously, it's the #1 mistake I see.

Websites and Online Sources

These are trickiest because websites change. Always include:

Author (if available)
Page title in quotation marks
Site name in italics
Full URL
Access date (crucial since pages disappear)

APA: Centers for Disease Control. (2022, March 15). COVID-19 vaccination guidelines. Retrieved June 5, 2023, from https://www.cdc.gov/covid/vaccines
MLA: "COVID-19 Vaccination Guidelines." Centers for Disease Control and Prevention, 15 Mar. 2022, www.cdc.gov/covid/vaccines. Accessed 5 June 2023.
Chicago: Centers for Disease Control and Prevention. "COVID-19 Vaccination Guidelines." Last modified March 15, 2022. https://www.cdc.gov/covid/vaccines.

See how APA puts "Retrieved from" while MLA says "Accessed"? These tiny differences matter. Learning how to write a citation means sweating these details.

Social Media Citations (Yes, They Count!)

Tweet at your professor? You might need to cite it:

APA: [@username]. (Year, Month Day). First 20 words of tweet [Tweet]. Twitter. URL
MLA: @username. "Full text of tweet." Twitter, Day Month Year, Time, URL

APA: [@neiltyson]. (2023, February 14). Remember when Pluto was a planet? Good times. #SpaceFacts [Tweet]. Twitter. https://twitter.com/neiltyson/status/123456
MLA: @neiltyson. "Remember when Pluto was a planet? Good times. #SpaceFacts." Twitter, 14 Feb. 2023, 2:15 p.m., twitter.com/neiltyson/status/123456.

I actually had to cite an Instagram Story for a digital culture paper last year. Weird? Yes. Necessary? Absolutely.

In-Text Citations: The Secret Handshake

These little parenthetical notes tell readers where a specific fact came from. Mess this up and your argument collapses.

Style	Direct Quote	Paraphrase
APA	(Smith, 2020, p. 42)	(Smith, 2020)
MLA	(Smith 42)	(Smith)
Chicago	(Smith 2020, 42)	(Smith 2020)

Notice MLA doesn't use commas or "p." before page numbers? That's the stuff that trips people up when figuring out how to write a citation.

Life-saving trick: Always put the period AFTER the parentheses when ending a sentence. Example: ...climate change impacts (Miller 2022). Not ...(Miller 2022.)

7 Deadly Citation Sins (And How to Avoid Them)

After grading hundreds of papers as a TA, I've seen it all. Here's what makes professors rage:

Sin #1: Missing page numbers for direct quotes. "Where did you find this?" written in angry red pen.
Sin #2: Fake URLs that lead nowhere. Test EVERY link before submission.
Sin #3: Alphabetical mess in bibliographies. APA/MLA require strict A-Z order by author's last name.
Sin #4: Inconsistent formatting. Don't mix APA commas with MLA italics.
Sin #5: Dropping "et al." improperly. APA: 3+ authors = first author + et al. every time.
Sin #6: Forgetting access dates for online sources. Web pages vanish!
Sin #7: Inventing citation rules. "I thought it looked cleaner" isn't a valid defense.

I once forgot to alphabetize references - professor wrote "Is this avant-garde formatting?" Ouch.

Citation Tools: Helpful or Hazardous?

Tools like Zotero or Citation Machine sound like lifesavers. But be careful:

Tool	Pros	Cons	My Verdict
Zotero	Free, saves sources, integrates with Word	Steep learning curve, sometimes glitches	Great for long projects
EndNote	Powerful, university licenses available	Expensive, overkill for small papers	Only if your school offers it free
Citation Machine	Simple, no installation needed	Ads everywhere, frequent errors	Double-check EVERY output

Honestly? I still manually check every citation generated by tools. They get journal titles wrong about 20% of the time in my experience. Knowing how to write a citation yourself is like knowing basic car maintenance - you'll catch problems before they cause disasters.

FAQ: Your Burning Citation Questions Answered

How detailed should citations be? I see some with full publisher addresses.

That's old-school Chicago style. Most formats now skip publisher locations unless it's critical (like historical documents). When in doubt, follow the style guide - APA 7th edition simplified this significantly.

Do I need to cite common knowledge?

If your reader is likely to say "duh" (e.g., water boils at 100°C), no citation. If they might ask "says who?" (e.g., 68% of college students procrastinate), cite it. When learning how to write a citation, when in doubt, cite.

How do I cite a source within a source?

Ah, the dreaded "quoted in." Try to find the original, but if impossible: APA: (Smith, 2015, as cited in Lee, 2020). Only include Lee in references. Chicago uses "quoted in" in footnotes.

Citation generators messed up my formatting. Am I still responsible?

Unfortunately, yes. Your professor won't accept "but Zotero did it!" as an excuse. Think of generators as spellcheck - helpful but not infallible.

How do I cite ChatGPT or AI-generated content?

This is evolving fast. APA says: describe prompt in text, add retrieval date and URL. Example: (OpenAI, 2023; see Appendix A). MLA suggests similar treatment. Check your institution's latest guidelines - rules changed three times last semester alone!

Parting Wisdom from My Citation Battle Scars

When I started learning how to write a citation, I hated every minute. Now? I appreciate how they create intellectual accountability. My final advice:

Build your references AS YOU RESEARCH. Don't wait until 2AM before deadline.
Buy the physical style guide for your field - sticky-note the common sources.
Triple-check DOI links - they're case-sensitive and punctuation-sensitive.
When stuck, find a similar source in your style's official examples.

Remember that paper where I botched the citations? Got a C after the professor docked points on every reference. The next paper? Perfect citations, A-. Small pain for huge gain. Now if you'll excuse me, I need to cite this article about citations...