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Encyclopedias & More: Citing Sources

Find specialized academic encyclopedia entries, dictionary definitions and more!

Citing Sources

 American Psychological Association Format (Purdue OWL)

This site created by the esteemed Purdue Online Writing Lab (OWL) provides help a guide to APA, the most commonly used format to cite sources within the social sciences.

AP Stylebook (Associated Press Stylebook)

The Web-based edition is a fully searchable version of the Associated Press Stylebook, including an A-Z guide to usage, spelling, and a pronunciation guide with audio files.

Chicago Style: Chicago Manual of Style Online

This online site provides access to both the 15th and 16th edition. Both editions are completely searchable, offering ready access to the complete guidelines and examples. Also included are a Style Citation Quick Guide, fully searchable Q&A files, as well as sample forms, letters, and style sheets.

MLA: Modern Language Association Format (Purdue OWL)

The MLA format is used by many disciplines in the humanities, most notably within the study of language and literature.

Citation Management Systems

If you are interested in tools that help you automatically generate and store citations, please look into web-based citation management systems.

Web-based citation management systems are tools often capable of the following:

  • Importing references/materials (including full-text) from library databases and catalogs, websites, files on your computer etc. directly into your own personal database within the system.
  • Generating individual citations or entire bibliographies in multiple citation styles.
  • Creating (and inserting) in-text citations for you as you type your paper.
  • Providing opportunity to annotate sources.
  • Allowing you to collaborate easily with other researchers online through sharing sources or citations.

Currently there is an array of citation managers available on the market (with new ones being released every year). The most popular ones at academic institutions and their libraries include the following:





OWL Purdue

The University of Purdue Online Writing Lab (OWL) provides over 200 free resources for writing including but not limited to materials for Writing and Teaching Writing, Research, Grammar and Mechanics, Style Guides, ESL (English as a Second Language), and Job Search and Professional Writing.

NIU Writing Center

This is a place for all writers at Northern Illinois University, undergraduates, graduates, staff, and even faculty, to talk about their writing with trained consultants, one-on-one.

Online Writing Tutorial (NIU)

The purpose of this tutorial is to help students quickly review common mistakes made in English grammar, punctuation, organization, and writing styles. It is not meant to be a comprehensive resource on writing practices. The tutorial is intended for self-paced learning by students. Faculty can use it as an educational resource to supplement their classroom discussions on effective writing practices.

Avoiding Plagiarism

NIU Online Tutorial on Academic Integrity for Students

The purpose of this tutorial is to promote academic integrity at Northern Illinois University by increasing students' awareness of the issues and offering strategies to protect themselves from academic dishonesty situations. This tutorial is intended for self-paced learning by students, and faculty can use it as an educational resource to supplement their classroom discussions on academic integrity.

NIU Statement on Plagiarism

This site provides NIU’s official statement on plagiarism.