How to Cite
We have established a direct correspondence between the reference numbers in the printed Handbook and the permalinks (permanent URLs) used on the DLMF website. This enables readers of either version to cite specific items and to easily lookup such cited items in either version.
The following table outlines the correspondence between reference numbers as they appear in the Handbook, and the URL’s that find the same item online. Note the ‘E’, ‘F’ and ‘T’ used to disambiguate equations, figures and tables.
Item Type  Ref. Number  Permalink 

Chapters  5  http://dlmf.nist.gov/5 
Sections  5.4  http://dlmf.nist.gov/5.4 
Subsections  5.4(iii)  http://dlmf.nist.gov/5.4.iii 
Equations  5.4.1  http://dlmf.nist.gov/5.4.E1 
Figures  5.3.1  http://dlmf.nist.gov/5.3.F1 
Tables  5.4.1  http://dlmf.nist.gov/5.4.T1 
To Find an Item
For example, suppose you have been referred to equation 5.2.1, or equivalently, given the URL http://dlmf.nist.gov/5.2.E1, eg. in an email. To find this equation in the printed Handbook, you would use the traditional method of turning to chapter 5, find section 2 within it, and then scan to the 1st equation. To find the equation in the web site, you can simply type the URL http://dlmf.nist.gov/5.2.E1 into the location bar of your browser.
To Cite an Item
Because of this correspondence, citations giving a reference number or URL will generally be more useful to your readers than the page number from the Handbook. This remains true whether you originally found the material in the Handook or the web, or whether the citation will appear in print or electronically.
For convenience, the recommended permalink can be found in the popup ‘Info box’ associated with each item in the site.
When referring to the web site from a print publication, it is recommended to use a format similar to the following:
 DLMF

NIST Digital Library of Mathematical Functions.
http://dlmf.nist.gov/, Release 1.0.10 of 20150807.
Online companion to [OLBC10].  OLBC10

F. W. J. Olver, D. W. Lozier, R. F. Boisvert, and C. W. Clark, editors.
NIST Handbook of Mathematical Functions.
Cambridge University Press, New York, NY, 2010.
Print companion to [DLMF].
The following BibTeX entries may be useful: citedlmf.bib.
Note that the entry for DLMF indicates the current DLMF release date and version. Since the site is occasionally updated and corrected, citations of DLMF will be most useful to your readers if they reflect the version in effect when you consulted it.
The current date and version can be found at the bottom of all DLMF pages.