What Is a Citation Style?

A citation style is a standardized method for acknowledging sources in academic writing. Each style specifies how to format in-text citations and reference lists, ensuring readers can locate your sources and verify your claims.

Different academic disciplines use different styles. Using the wrong style—or inconsistent formatting—can cost you marks or lead to desk rejection from journals.

Quick Reference: Which Citation Style Should You Use?

Not sure? Check your assignment guidelines or journal's author instructions. When in doubt, ask your instructor.

The Two Main Citation Systems

Author-Date Systems

You cite sources with the author's name and publication year in parentheses: (Smith 2023). The reference list is alphabetized.

Styles using this system: APA, Harvard, ASA, Chicago (one option), Turabian (one option)

Numbered Systems

You cite sources with numbers—either in brackets [1] or superscript¹. The reference list follows citation order, not alphabetical order.

Styles using this system: IEEE, AMA, Vancouver, ACS, Bluebook, Chicago (one option)

Citation Styles by Field

Sciences

• Psychology & Social Sciences → APA

• Chemistry → ACS

• Engineering & Computer Science → IEEE

• Medicine & Health → AMA or Vancouver

Humanities

• Literature & Languages → MLA

• History & Arts → Chicago or Turabian

Social Sciences

• Sociology → ASA

• General Social Sciences → APA

Professional Fields

• Law → Bluebook

• Business → Usually APA or Harvard

By Region

• UK & Australia → Harvard (most common)

• US → Varies by discipline

• Medical journals worldwide → Vancouver

What Every Citation Includes

Regardless of style, citations typically require:

For books: Author, title, publisher, year

For journal articles: Author, article title, journal name, volume, issue, pages, DOI

For websites: Author (if any), page title, site name, URL, access date (some styles)

The difference between styles is how you format and arrange these elements.

Common Citation Mistakes

Using the wrong style — Always verify requirements before you start writing.

Inconsistent formatting — Mixing styles or formats within a paper is a red flag.

Missing DOIs — Most styles now require DOIs for journal articles when available.

Forgetting in-text citations — Every source in your reference list needs at least one in-text citation, and vice versa.

Relying solely on generators — Citation tools make errors. Always verify output against official guidelines.

Frequently Asked Questions

What's the difference between a citation and a reference? A citation is the brief in-text marker (like "(Smith 2023)" or "[1]"). A reference is the full entry in your reference list with complete source details.

Can I switch citation styles mid-paper? No. Use one style consistently throughout your entire document.

Do I need to cite common knowledge? No. Facts that are widely known and uncontested (e.g., "Water freezes at 0°C") don't require citations. When in doubt, cite.

How do I cite a source I found in another source? This is called a secondary citation. Most styles have specific formats—search your style guide for "secondary source" or "as cited in."

What if my source is missing information? Each style has rules for missing authors, dates, or other elements. Check the specific guide for your style.

Citation Tools and Resources

Official style manuals — Always the authoritative source. Links provided in each guide above.

University library guides — Most libraries publish free guides tailored to their institution.

Reference managers — Tools like Zotero, Mendeley, and EndNote can help organize sources and generate citations (but always verify output).

Research workspaces — Platforms like Wonders help you find, organize, and cite academic sources in one place.

Next Steps

1. Identify your required style from your assignment or target journal

2. Read the specific guide for that style (linked in the table above)

3. Bookmark the official manual for reference

4. Set up your reference manager with the correct output style

5. Verify your citations before submission

Need help finding and citing academic sources? Wonders is an AI research workspace that helps you discover relevant papers and export properly formatted citations.