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Reference List
References should be provided on a separate page at the end of your paper, with the title “References” at the top of the page. They should be listed and numbered in order of citation, not alphabetically. The numbers should be flush against the left margin, and separated from the body of the reference.
Some general notes on the format of references:
- Authors are always referred to by their surname and initials. Suffixes such as “Jr.” or “III” are included, but separated by a comma – e.g. “E. C. M. Boyle, III”.
- Any IEEE journals cited should be referred to by their official abbreviations, as listed by IEEE here.
- For references with up to six authors, list all authors in the order they are presented in the publication’s byline. Use the format “A. B. Author, C. D. Author, and E. F. Author”.
- For publications with seven or more authors, list the first author followed by “et al.”
- Titles of books, journals, and publications of similar size are set in title case.
- Titles of articles, technical reports, and publications of similar size are set in sentence case.
- If you are unsure whether to use sentence case or title case, err on the side of following the original capitalization.
- Names of months are shortened to 3-4 letters each: Jan., Feb., Mar., Apr., May, June, July, Aug., Sept., Oct., Nov., Dec.
Books
The basic format for a book citation is as follows. As per usual, please note that any information not relevant to your citation should simply be left out – e.g., if there is only one edition of the book you are citing, don’t bother specifying “1st edition”.
If the book was accessed online, add “[Online]”, accompanied by the URL and date accessed, as follows:
Translators and editors can be added after the title, identified by the abbreviations “Trans.” or “Ed.”
If the volume is titled separately from the overall work, you can add the title of the series after the title of the volume.
To cite a specific chapter or section, add the title of the chapter/section before the book title, and include the chapter/section number and page range at the end. Use the abbreviations “ch.”, “sec.”, and “pp.”
Periodicals
Citing an article from a journal or other periodical is largely the same as citing a chapter in a book, as above – the only major difference is that one does not need to include a publisher when citing a periodical. One should, however, remember to check for official abbreviated versions of a journal’s title, especially if they are IEEE journals. Also, do include a Digital Object Identifier (DOI) whenever one is available.
Some periodicals use an “Article ID” rather than a DOI. In your reference list, treat this the same as a DOI, but label it “Art. no.” rather than “doi:”.
Any articles in another language should be presented with their title translated into the language of your paper, but with a parenthetical notation that they are, in fact, in another language so as to save your readers the trouble of tracking down an article only to find out they cannot read it.
However, an article that was originally written in another language but translated by someone else should have the translation information in parentheses at the end of the entry. The format of said information will vary depending on where the translation was printed – it should be essentially written as an entire reference entry in itself, just without a number.
Websites
The citation format for a website is straightforward, provided you remember that, if any information is unavailable (e.g. if a website lists no author), you can simply leave that out of your citation. You should also be willing to clean up the titles of webpages and websites if necessary – e.g., some web sources will have their titles set in all caps, but you need not retain that capitalization in citations.
Theses and Dissertations
The following guidelines apply to theses for bachelor’s or master’s degrees, as well as to PhD dissertations; these sources should, of course, only be used if there is not a formally-published version of the work, but often the only way to access certain information is through repository copies of dissertations.
Since they are not formally published, all publication information is replaced with information about the university department to which they were submitted. Note that names of departments and universities may be abbreviated wherever reasonable. It is also necessary to specify the distinction between a dissertation and a thesis. Where the template below has “document type”, you should not only specify one or the other, but also note the type of degree sought with said document – e.g. “B.S. thesis” or “PhD dissertation.”
In addition to the usual rule about the “state” field being optional if the document is from outside the United States, you should also omit the “state” field if the name of the state is contained within the name of the university – there is no need to specify that, for instance, the University of Maryland is located in Maryland. You do, however, have to retain the “city” field.
Note that if you are accessing this thesis or dissertation in an online repository, you must also include the URL, but an access date is optional.
Conferences and Presentations
To cite a presentation given at an academic conference, you must cite the name of the conference as well as the location where it took place. You should also include the date(s) on which the conference occurred. If the paper being presented has a “Paper Number”, as given at some IEEE conferences, then you should include that at the end of the citation. Conference names should be abbreviated where feasible.
Citing conference proceedings follows the same rules as citing any other periodical, with two exceptions. First, if the proceedings list an editor, they should be included. Second, you should include the location of the conference if known to you. If the conference proceedings you are citing have separate volume and series titles, follow the guidelines for volume/series distinctions under the Books section.
Note that the date in this citation is the publication date given for the proceedings, not the time of the original conference.
If the source is found online, include the URL or DOI as normal.
You may also cite a lecture or presentation given elsewhere, but it is encouraged that you only do so if the content of said lecture or presentation is available somewhere for your readers to see for themselves – otherwise, it’s not much of a source. IEEE guidelines presume that either the lecture or the lecturer’s notes are available online, and the citation is formatted as such.
In the case of lecture notes, you must specify the medium or the type of file – e.g., “PowerPoint slides” or “Plain Text Document”. If the full lecture is online as a recording, then the “Medium” field should simply read “Online”.
Technical Reports
To cite a technical report, you must cite not only the author and title, but the company, university, or other institution behind the report – such things are vitally important when citing information that has not been through the academic peer-review process. You should also cite the date and the report number.
Note that the name of the institution should be abbreviated where possible – e.g. “Corp.” rather than “Corporation”. However, particularly when the institution in question is a university, you should try to include the name of the department or laboratory within the university responsible for the report – much like when citing a dissertation.
Datasets
When using raw data compiled by someone else, you must cite the distributor, a URL or DOI, and a date accessed. If there are different versions of the dataset, be sure to include the version number in the title.
If the original compilers of the dataset have published their own paper on their results, it is generally wise to read and cite that source as well.
Government Documents
Generally, this refers to laws, bills, or similar. Government reports would fall under the “Reports” section above. Note that variation in format may be necessary when citing from governments outside the USA.
Manuals and Handbooks
The citation format of a manual varies slightly depending on whether it is being accessed in print or online. If it is online, the format is dependent on whether it is credited to a single author or to the institution as whole. The variants are as follows:
Patents
In the event you need to cite a patent document, the format is straightforward. You want the author, the patent title, the patent number, and the date it was filed. Note that patent numbering is specific to the country in which they were filed, so it is necessary to include the country in the patent number.
Unpublished Materials
There are a few different situations in which an unpublished document might need to be cited. If you are working with a paper that has yet to be published, but is being unofficially circulated – a situation that is fairly common given the long wait times involved in official publication – you should cite it as a normal journal article, but replace the specific volume / date information with “to be published”.
If the article has yet to even be accepted by a specific journal, replace all publication information with “submitted for publication”.
Perhaps you have access to a paper that is not even submitted for publication. In that case, it is simply cited as follows:
If the paper you want to cite is publicly available through an organization less official than a peer-reviewed journal, such as a paper repository or an open-access, non-peer-reviewed database, then you should specify where it can be found. This could be a URL, the name of a repository (include a paper number if available), or whatever other information seems necessary.
Another common form of unpublished reference is a “private communication”. If you’ve spoken to an expert in the field, in person or otherwise, and received insights that have not yet been published, you may cite them as follows:
(Our example continues to use the term “author” out of convenience, even if the reference in question is not written down.)
- Navigation
- Purdue OWL
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General Writing
- General Writing Introduction
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The Writing Process
- The Writing Process Introduction
- Writing Task Resource List: What Do You Need To Write?
- Invention: Starting the Writing Process
- Prewriting (Invention)
- Writer's Block
- Stasis Theory
- Creating a Thesis Statement, Thesis Statement Tips
- Developing an Outline
- Reverse Outlining
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Academic Writing
- Academic Writing Introduction
- The Rhetorical Situation
- Establishing Arguments
- Logic in Argumentative Writing
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Common Writing Assignments
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Mechanics
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- Capitals: Help with Capitals
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Grammar
- Grammar Introduction
- Spelling: Common Words that Sound Alike
- Numbers: Writing Numbers
- Adjective or Adverb
- How to Use Adjectives and Adverbs
- Appositives
- Articles: A versus An
- How to Use Articles (a/an/the)
- Prepositions
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- Subject/Verb Agreement
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Punctuation
- Punctuation Introduction
- Punctuation
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- Independent and Dependent Clauses
- Conquering the Comma Presentation
- Commas
- Apostrophe Introduction
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Visual Rhetoric
- Visual Rhetoric Introduction
- Visual Rhetoric
- Analyzing Visual Documents
- Using Fonts with Purpose
- Color Theory Presentation
- Designing Effective PowerPoint Presentations
- Data Visualization
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Undergraduate Applications
- Undergraduate Applications Introduction
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Graduate School Applications
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- Overview
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OWL Conversations
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Research and Citation
- Research and Citation Resources
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Conducting Research
- Conducting Research Introduction
- Research Overview
- Conducting Primary Research
- Evaluating Sources of Information
- Searching Online
- Internet References
- Archival Research
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Using Research
- Using Research Introduction
- Writing with Statistics
- Strategies for Fair Use
- Quoting, Paraphrasing, and Summarizing
- Paraphrase Exercises
- Avoiding Plagiarism
- Writing Scientific Abstracts Presentation
- ASA Style
- Resources for Documenting Sources in the Disciplines
- Citation Style Chart
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APA Style
- APA Style Introduction
- APA Overview and Workshop
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APA Formatting and Style Guide
- General Format
- In-Text Citations: The Basics
- In-Text Citations: Author/Authors
- Footnotes and Endnotes
- Reference List: Basic Rules
- Reference List: Author/Authors
- Reference List: Articles in Periodicals
- Reference List: Books
- Reference List: Other Print Sources
- Reference List: Electronic Sources
- Reference List: Other Non-Print Sources
- Additional Resources
- Types of APA Papers
- APA Stylistics: Avoiding Bias
- APA Stylistics: Basics
- APA Headings and Seriation
- APA PowerPoint Slide Presentation
- APA Sample Paper
- APA Tables and Figures 1
- APA Tables and Figures 2
- APA Abbreviations
- Statistics in APA
- APA Classroom Poster
- APA Changes 6th Edition
- General APA FAQs
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MLA Style
- MLA Style Introduction
- MLA Overview and Workshop
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MLA Formatting and Style Guide
- General Format
- MLA Formatting and Style Guide
- MLA In-Text Citations: The Basics
- MLA Formatting Quotations
- MLA Endnotes and Footnotes
- MLA Works Cited Page: Basic Format
- MLA Works Cited Page: Books
- MLA Works Cited Page: Periodicals
- MLA Works Cited: Electronic Sources
- MLA Works Cited: Other Common Sources
- MLA Additional Resources
- MLA Abbreviations
- MLA Sample Works Cited Page
- MLA Sample Paper
- MLA Tables, Figures, and Examples
- MLA PowerPoint Presentation
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- MLA Classroom Poster
- MLA 8th Edition Changes
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Chicago Style
- CMOS Introduction
- CMOS Overview and Workshop
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CMOS Formatting and Style Guide
- Chicago Manual of Style 17th Edition
- General Format
- Books
- Periodicals
- Web Sources
- Audiovisual Recordings and Other Multimedia
- Interviews, Personal Communication
- Legal, Public and Unpublished Materials
- Bluebook Citation for Legal Materials
- Miscellaneous Sources
- CMOS Author Date Sample Paper
- CMOS NB Sample Paper
- CMOS NB PowerPoint Presentation
- CMOS Author Date PowerPoint Presentation
- CMOS Author Date Classroom Poster
- CMOS NB Classroom Poster
- IEEE Style
- AMA Style
- ASA Style
- Using Citation Generators Responsibly
- Using Paper Checkers Responsibly
- Style Manual Glossary
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Teacher and Tutor Resources
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Writing Instructors
- Writing Instructors Introduction
- Parents
- Grades 7-12 Instructors and Students
- Non-Purdue Users
- Purdue Instructors and Students
- Adult Basic Education
- Writing Across the Curriculum: An Introduction
- Creative Nonfiction in Writing Courses
- Poetry in Writing Courses
- Teaching Detailed Writing and Procedural Transitions
- Teaching OSDDP: A Guide for Professional Writing Instructors
- Email Etiquette for Professors
- Writing Letters of Recommendation for Students
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Writing Tutors
- Writing Tutors Introduction
- Purdue Writing Lab Quick Tour
- Meeting One-on-One with Students
- Tutoring a Résumé
- Tutoring Cover Letters
- Tutoring Creative Writing Students
- Tutoring Lab Reports
- Tutoring Grammar
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Teaching Resources
- Teaching Resources
- Conducting an Interview Presentation
- Writing Workshops for Graduate Students
- Writing Process Presentation
- Organizing Your Argument Presentation
- Peer Review Presentation
- Visual Rhetoric Slide Presentation
- Writing a Literary Analysis Presentation
- Effective Persuasion Presentation
- Teaching and Assessing Grammar
- Analytical Research Project Presentation
- Conducting an Interview Presentation
- Job Acceptance Letter Presentation
- Invention Presentation
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Preventing Plagiarism
- Preventing Plagiarism Introduction
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Contextualizing Plagiarism
- Contextualizing Plagiarism
- Truth or Consequences
- Handout: Truth or Consequences
- The Big Picture
- Authorship and Popular Plagiarism
- Copyright and Plagiarism
- Handout: Copyright and Plagiarism
- Collaborative Authorship
- Handout: Collaborative Authorship
- Defining Our Terms
- Class Plagiarism Policy
- Comparing Policies
- Handout: Comparing Policies
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Avoiding Plagiarism
- Avoiding Plagiarism
- Summarizing, Paraphrasing, and Quoting
- Peer Summarizing
- Anonymous Paraphrasing
- Paraphrasing from Media
- Handout: Paraphrasing from Media
- Using In-text Citations
- Handout: Using In-text Citations
- Quoting Others
- Handout: Quoting Others
- Summary, Paraphrase, and Quotation in Context
- Handout: Summary, Paraphrase, and Quotation in Context
- Translingual Writing
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Writing in the Engineering Classroom
- Why Include Writing in Engineering Courses?
- Using Bloom’s Taxonomy
- Types of Writing Assignments for Engineering Courses
- Conceptual Writing Prompts
- Explain-a-Problem Writing Prompts
- How Stuff Works Writing Prompts
- Real-World Example Writing Prompts
- Design-a-Problem Writing Prompts
- Open-Ended Design Writing Prompts
- Writing Tips for Students
- Assessment and Feedback of Engineering Writing
- Research Team
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Writing Instructors
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Subject-Specific Writing
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Professional, Technical Writing
- Professional, Technical Writing Introduction
- Workplace Writers
- Effective Workplace Writing
- Audience Analysis
- Prioritizing Your Concerns for Effective Business Writing
- Parallel Structure
- Activity and Postmortem Reports
- Tone in Business Writing
- HATS: A Design Procedure for Routine Business Documents
- Basic Business Letters
- Accentuating the Positives
- Memos
- Four Point Action Closing
- Grant Writing
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Professional, Technical Writing