Books

Place edition information after the title.

Express numbers representing editions in arabic ordinals, as first becomes 1st, IV becomes 4th. 

Abbreviate the word "edition" and other descriptive words:

• New revised edition becomes New rev. ed.
• Eighth American Edition becomes 8th Am. ed.
• Third edition becomes 3rd ed.

End with a period.

Schott J, Priest J. 2002. Leading antenatal classes: a practical guide. 2nd ed. Boston (MA): Books for Midwives.

Electronic publications

Words expressing edition for electronic publications are not as widely known and are not abbreviated (29.3.7.12 and 29.3.7.13).

Version 2.0, Update 6.1

Sample end reference:

IMGT/HLA Sequence Database [Internet]. 2003. Release 2.9.0. Cambridge (England): European Bioinformatics Institute. [updated 2005 Jun 1; cited 2005 Jun 22]. Available from: https://www.ebi.ac.uk/imgt/hla/.

Journals and Newspapers 

Editions for journal titles and newspapers are usually published simultaneously and are considered part of the title. Place the abbreviated edition (capitalized) in parenthesis following the title proper. End the complete title with a period.

Journal: BMJ (Int Ed.).

Newspaper: Washington Post (Final Ed.).