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Bluebook Legal Citation System Guide


This is a guide to the Bluebook system of American legal citation. The information here can help anyone who is writing a scholarly legal paper in the United States, including JD students, LLM students, and SJD students.

The Bluebook is currently in its 21st edition, released in June 2020. It is available in two formats: as a print book, and as an electronic publication.  To buy a print copy or a subscription to the electronic version, visit

All references to print book page number in this guide are from the 21st edition.

Note: Looking for legal citation systems beyond the Bluebook?  Scroll down to check out the list under "Over It? Here are Some Other Options..."

Learning the Bluebook

Bluebook Class Training Video (Pre-Pandemic Version)

NOTE: Jennifer has updated her Bluebook class for LLM students for the 2021-22 academic year and will be offering it over Zoom.  It now includes a shorter lecture and an in-class group exercise.  If you are a current HLS LLM student, you can register for the class by visiting the law library's training calendar at


Below is a two-part recording of a Bluebook training class offered by Jennifer in March 2020. Although it references the 20th edition of the Bluebook, the class is still relevant and provides a good basic introduction to general Bluebook style and citation rules for US and foreign sources. 

Contact a Research Librarian

If you need help navigating the Bluebook or are not sure how to cite a particular source, you are welcome to contact a research librarian for help.  Visit for information about how to get in touch with us.

Bluebook Tips Video Series

We have some short videos of Bluebook tips that are based on the FAQ in this guide.  

The first tip video explains the answers to both FAQ #3 (using id and supra) and FAQ #4 (using Word's internal cross reference feature), all in one 3:30 video!

The next tip video discusses FAQ #2 - using rule 18 to cite online sources.  It also talks about, the Harvard Law School Library Innovation Lab's website archival tool. 

Here's another video that was made based on a recent question we received in the research service department.  It describes how to cite a federal statute as a session law (using rule 12.4) and not how it was codified in the U.S. Code.  Examples are given for two types of citations: to a chapter number (for very old statutes), or to a public law number (for newer statutes).

The Bluebook: An Overview

The Bluebook has two sections:

  • The Bluepages section: citation rules for documents written by practitioners, like legal memoranda and court filings. 
  • The Whitepages section: citation rules for legal academic publications, including law journal articles.

Since law school work focuses on academic writing, this guide describes and explains the rules in the Whitepages section.

Citation Rule Categories

  • Rules 1-8 (pp. 61-94): Style rules, including typeface, capitalization, abbreviation, quotations, and cross references.  
  • Rules for citing primary sources:
    • Rule 10 (p. 95): Cases
    • Rule 11 (p. 119): Constitutions 
    • Rule 12 (p. 120): Statutes, Codes, and Session Laws
    • Rule 13 (p. 135): Legislative Materials (including Congressional documents)
    • Rule 14 (p. 142): Administrative and Executive Materials
  • Rules for citing secondary sources:
    • Rule 15 (p. 147): Books, Reports, and other Nonperiodic Materials
    • Rule 16 (p. 157): Periodical Materials (including journal articles and newspapers)
    • Rule 17 (p. 169): Unpublished and Forthcoming Sources
  • Rules for citing non-print sources, including internet and other electronic sources: Rule 18 (p. 174)
  • Rules for citing foreign (non-U.S.) materials: Rule 20 (p. 188)
  • Rules for citing international materials: Rule 21 (p. 195)


Table 1 (p. 227) has jurisdiction-specific rules for citing U.S. federal and state cases, statutes, and other primary legal materials.

Table 2 has rules for citing sources from selected foreign jurisdictions.  It is no longer in the print version of the Bluebook, but it is freely available online at

Tables 3 (international organizations, p. 299) and 4 (treaties, p. 302) have rules for citing international sources.

Finally, many Bluebook rules require certain names, words, and phrases to be shortened.  Tables 6-16 (starting on p. 304) list these abbreviations.

Frequently Asked Questions (FAQ) for the Bluebook

Below is list of questions we are often asked about the Bluebook.  Answers, with examples, are provided.

FAQ #1: Does the Bluebook have a list of citation examples for each rule?

Yes! Right inside the front cover there is a quick guide to the major rules, with citation examples. Use this as a quick reference if you can't remember which rule covers which type of source.

FAQ #2: How do I cite something I found online?

Rule 18 has rules for citing internet sources, websites, documents found online, blogs, social media posts, etc. 

Remember, the Bluebook really prefers that you cite to a print source. It has gotten more flexible over the years. However, for something like a law review article, even if you found it online, you still need to follow the instructions in Rule 16 to cite it.

FAQ #3: How do I cite a source that I cited in another footnote?

Instructions for doing this are in Rule 3.5: Internal Cross-References.


If you cited only one source in footnote #1, and you want to cite the exact same source in footnote #2, that is when you use id. Only the source has to be the same, not the page or section.


For secondary sources like law review articles and books, if you want to cite a source that you cited longer ago in your paper than the previous footnote, you can use supra.

When you do a supra citation, you have to use the same font specifications as you did in the original citation. What does that mean? If you cited a book in the earlier footnote, you put the author's name in small caps. You have to do the same thing in the supra footnote. Footnote #7 in the example below illustrates this.

TIP: There are two ways to change text to small caps. Select the text. Then, either (a) access the Font edit window and select Small caps under Effects, or (b) press these keys at the same time: Ctrl + Shift + K.


"Short Forms" for Primary Sources

So what if you want to cite a case (or other primary source) that you have cited before? You cannot use supra for that. Instead, you have two options:

  • If you cited the case within the previous five footnotes, you can use a "short form" to cite the case in the current footnote. "Short form" rules for primary sources are at the end of each rule section (for example, short forms for cases is listed in rule 10.9 on page 115). This is shown in footnote #10 in the example below.
  • If you cited the case more than five footnotes ago, you have to cite the whole case again. This is shown in footnote #8 in the example below.

FAQ #4: Help! When I add new footnotes, the numbering in supra citations gets messed up.

Most LLM papers are in a constant state of flux until they are turned in. Adding footnotes can be a problem if you already have supra references. In the example below, footnote #5 was just added. It cites a different law review article.

Take a look at footnotes #8 and #10 now. The Jackson book is no longer in footnote #5 after this addition, it's now in footnote #6. If you have 200 footnotes already done in your paper, you will have to go back and find each one that cites the Jackson book and change the 5 to a 6. What a pain!

Instead, what you should do from the start is use Microsoft Word's internal cross-reference feature. It's great! Here's how it works.

  1. Enter the first part of your footnote text, up to the word "note."
  2. On the Insert bar, click Cross-reference.
  3. In the Reference Type menu, select Footnote.
  4. Make sure that Footnote number is selected in the Insert reference to menu.
  5. Select the footnote you want to refer to in the footnote list.
  6. Click Insert.

If you do this, then it is very easy to update all the footnote number references later. Simply click in any footnote, press the Ctrl and A keys at the same time to select all the footnote text, and press the F9 key.

FAQ #5: When should I use "see" in a footnote?

Introductory signals explain why and how you are citing and using a source.They are listed below, and rule 1.2 explains their use.

  • E.g.
  • Accord
  • See
  • See also
  • Cf.
  • Compare
  • Contra
  • But see
  • But cf.
  • See generally

When using a signal, you may want to add information explaining why you are citing a particular source. See rule 1.5: Parenthetical Information, for how to do this.

Footnotes #13 and #14 have been added to the example (below) to show how signals and parentheticals are used.

FAQ #6: How does "hereinafter" work?

Rule 4.2 (p. 81) explains both supra and hereinafter.

One use of hereinafter is if you cite two sources by the same author in the same footnote. You will need a way to distinguish them in later supra references. This is when hereinafter can come in handy. See footnotes #15 and #16 in the example below.

You may be asking why you can't use id. in footnote #16 above. Remember, you can only use id. if the previous footnote cited only one source.

FAQ #7: Are there special rules for citing non-English foreign sources?

Instructions for citing foreign (non-English) materials are provided in detail in Rule 20.2 and in the individual country sections in Table T2.

Tip: Note that these rules sometimes overlap and contradict each other; do your best to follow the examples. Remember, the purpose of citation is to make it as easy as possible for someone to find your cited source. If adding additional information to your citations will help your reader, then do it even if it's not in the Bluebook.


Generally, when it comes to language version, you need to cite the source you are referring to, as detailed in rules 20.2.2 and 20.2.5.

  • If you are referring to a non-English source in its original language, you need to cite the original-language version (see footnote #17 in the example below).
  • If you are referring to a source that was translated into English, you need to cite the translated version (see footnote #18 in the example below).

In creating these two examples, the following rules were consulted (and some judgment calls were made):

  • Rule 20.2.5: Citations to Translations of Non-English-Language Documents
  • Rule 20.4: Constitutions (foreign)
  • T2.14: Germany (Constitution)
  • T2.23: Italy (Constitution)
  • Rule 15: Books, Reports, and Other Nonperiodic Materials
  • Rule 18: The Internet, Electronic Media, and Other Nonprint Resources

These examples may create more questions than they answer. For example, the German Basic Law is cited in small caps, whereas the Italian constitution is not (and, perhaps, should be). In this case, each of those citations were created according to the jurisdictional rules in T2.

Remember, just do your best.

Cite foreign books just like U.S. books according to rule 15. For articles from foreign periodicals and newspapers, see rule 20.6. They are illustrated in footnotes #19 and #20 below.

Providing an English-language translation of foreign-language article titles is allowed, but not necessary. There is no stated rule on that topic for books.

FAQ #8: Are there special capitalization rules for titles?

The Bluebook's capitalization rule, Rule 8, states the following regarding capitalization of words titles:

  • General rule: capitalize all words, including the initial word and the word immediately following the colon.
  • Exception to the general rule: do not capitalize the following:
    • Articles (such as a, an, the)
    • Conjunctions (these are words that connect words, sentences, or phrases, such as for, and, nor, but, or, yet, so)
    • Prepositions (such as with, by, in, on)
  • Exception to the exception: Capitalize any of those words if they are the first word of the title, the first word after a colon, or more than four letters.

Incorrect article title:
Hearing the voiceless: a respected judge on putting the rights of crime victims above those of defendants

Correct article title:
Hearing the Voiceless: A Respected Judge on Putting the Rights of Crime Victims Above Those of Defendants

FAQ #9: Where do I put the footnote numbers in the text, before or after the punctuation?

In the text of the article, place the footnote number after any punctuation, including periods, commas, quotations marks, etc.

Over It? Here Are Some Other Options...

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