how do I cite a publication date with a revised edition
Each edition of a book should have a different publication date, therefore you will have only one publication date per citation. You should be able to find this date on the title page of the book, or on its reverse side. If you are still in doubt, you could double check the publication information by looking up the book in WorldCAT, which is available on this library page - http://libguides.css.edu/content.php?pid=219498&sid=1824679
An example of citing an edition can be found on this library page - http://libguides.css.edu/content.php?pid=61826&sid=454606
Your parenthetical/in-text reference would reflect the date of the edition you are using.