Bluebook R. 18 covers how to cite to the Internet and other electronic resources. Generally, the Bluebook encourages citation to print sources when they are available. Any online source that shares characteristics with a print source should be cited according to the rule for the print version.
Citing Directly to the Internet
There are three general formats for structuring a citation. These three general formats are 1) cite the same way you would cite to the hard copy print material, 2) citations that combine the print citation with the electronic citation and 3) citations directly to the electronic version.
1. Use the Print Citation - R. 18.2.1(a)
Bluebook requires citing to print, unless print is impossible to find, or unless there is a digital source that falls under one of these three categories. If the source falls under one of these three categories, cite to the internet source the same way you would cite to the print source:
1) Authenticated Documents (R.18.2.1(a)(i)): Electronic documents that have a certificate or logo indicating that a government entity has verified that the electronic document is complete and unaltered, as well as comparable to the print version. If the website or internet document you are viewing has such a certificate or logo, you can cite it as if it were a hard copy.
Here is an example of what the GPO seal of authenticity looks like:
For more information on authenticated documents, click here.
2) Official Versions (R.18.2.1(a)(iii)): Some states provide an online version of a document as the "official" document. An official document that is published only online can still be cited as if it were were print material if no authenticated version exists.
3) Exact Copies (R.18.2.1(a)(iii)): If the material posted online is an exact copy of the print version, such as a pdf with page numbers, you can cite to it as if it were the hard copy print source. Material from a commercial database such as Westlaw does not preserve the original pagination and therefore cannot be cited as if it were the print hard copy. You will follow Rule 18.3 for those.
For example, exact pdf copies of law review articles you find on the web can be cited as if citing to the print. Follow Bluebook R. 16.
2. Combination of print and electronic citation R. 18.2.1(b)
Any online source that shares the characteristics of the print source (such as a pdf) can be cited according to the Bluebook Rule for the print version. Add the URL after the print citation if:
(i) The print source is so obscure as to be unavailable or adding the url will substantially improve access OR
(ii) Even if it is unknown whether the cited information is available in print, if the online source shares print characteristics and can be cited according to a Bluebook rule other than Rule 18, cite as if to the print source and append the url.
3. Electronic Citations
If you find an electronic source that does not fit the citation format of any other rule, you can cite directly to the electronic material itself.
The elements of an electronic citation are:
Author (if available)
Title of the webpage within a website (unless you are just citing to the homepage of the website) - Use title bar or page-identifying heading
Include main page (home page) title and abbreviate it per T. 10 & 13 (use large & small cap font)
Use dates that refer clearly to the material cited (for blogs and news articles, include time-date stamp)
Otherwise use last updated or last modified date as it appears on the website
Or if none of the above exists, last visited date (the last date you visited the site.)
URL (but not if it is too long or complicated -- use the root URL if that is the case and append a parenthetical)
Rule 16.6(f) states that an online version of a newspaper can be used to replace print. Cite according to Rule 18.2.2. The citation should have: Full author(s) name, Title of the Article, Newspaper title in small caps(abbreviated according to T. 10 and T. 13), Full Date (and time, if there is one), followed by the url.
Example: Reuters, Trump Questions Lawmakers’ Efforts to Curb Asset Seizures by Police, N.Y. Times, (Feb. 7, 2017, 2:57 PM), https://www.nytimes.com/reuters/2017/02/07/us/politics/07reuters-usa-trump-police.html?_r=0.
Bluebook R.18.2.1(d): Perma.cc
The 20th Edition of The Bluebook Rule provides some examples of how to include a Perma.cc archive link.
Rule 18.2.1(d) re archiving provides this example: