Citing Sources

In addition to frequently-used styles such as APA, Chicago, MLA, and Turabian, several other citation styles are commonly used in the United States, often depending on the discipline, publication, or professional organization. Some specialized disciplines have created their own styles. Multiple professional and scholarly organizations, for example, developed style and publication guidelines especially adapted to their particular disciplines.

This page highlights some of the unique style manuals and style guides used within science, technology, sociology, law, and other disciplines.

ACM Style (Association for Computing Machinery)

Used in: Computer Science and related fields

Online Resources:

• Citation Style and Reference Formats

ACS Style (American Chemical Society)

Used in: Chemistry and related sciences

Online Resources:

• ACS Style Quick Guide
• ACS Style Guide
• ACS Style (USC Libraries)

Print Resources:

AIAA Style (American Institute of Aeronautics and Astronautics)

Used in: Aeronautics and Astronautics

Online Resources:

• Reference Style and Format

AIP Style  (American Institute of Physics)

Used in: Physics

Online Resources:

• AIP Style Manual

AP Style (Associated Press)

Used in: Journalism and news publications

AP style is used for writing in journalism. Sources are typically cited within the story or narrative, instead of in an official bibliography or footnotes, so there is no one format used to cite information. Details about writing in AP style can be found at the AP Stylebook.

Online Resources:

• Associated Press Stylebook (Purdue OWL)

Print Resources:

APSA Style (American Political Science Association)

Used in: Political science

Online Resources:

• References - APSA Style Manual

Print Resources:

ASA Style (American Sociological Association) 

Used in: Sociology

Online Resources:

• ASA Style quick tips (PDF)
• ASA Style (Purdue OWL)

Print Resources:

ASCE Style (American Society of Civil Engineers)

Used in: Civil Engineering

Online Resources:

• ASCE Style (USC Libraries)
• ASCE Citation Format (CalPoly Pomona Library)

Bluebook Style

Used in: Law and legal studies, with a focus on legal citations (cases, statutes, regulations, court documents)

Online Resources:

• Quick Style Guide: The Bluebook
• Bluebook Citation for Legal Materials (Purdue OWL)
• Introduction to Basic Legal Citation

Print Resources:

CSE Style (Council of Science Editors)

Used in: Life Sciences and Natural Sciences

Online Resources:

• The CSE-Style Citation Quick Guide
• CSE Style (USC Libraries)
• Council of Science Editors Documentation Style

Print Resources:

GSA Style (Geological Society of America)

Use in: Geology

Online Resources:

• Reference Guidelines and Examples (Geological Society of America)
• GSA Style (USC Libraries)

IEEE Style (Institute of Electrical and Electronics Engineers)

Used in: Engineering, computer science, and technology

Online Resources:

• How to Cite References: IEEE Documentation Style
• IEEE Reference Style Guide for Authors
• IEEE Style (Purdue OWL)
• IEEE Style (USC Libraries)

NLM Style (National Library of Medicine)

Used in: Medicine and Health Sciences. The official style manual for the National Library of Medicine, and suggested when citing documents from the associated databases MedLine and PubMed.

Online Resources:

• Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers
• NLM Style Quick Guide