If the source carries a notation indicating that it is a version of a work released in more than one form, identify the version in your entry. Books are commonly issued in versions called editions. A revised version of a book may be labeled revised edition or be numbered (second edition, etc.). Versions of books are sometimes given other descriptions as well.
Ex. The Bible. Authorized King James Version, Oxford UP, 1998.
Ex. Cheyfitz, Eric. The Poetics of Imperialism: Translation and Colonization from The Tempest to Tarzan. Expanded ed., U of Pennsylvania P, 1997.
From MLA Handbook, 9th ed., Ch. 5.48 Version: What It Is