For eBooks, the format is the same as the print book plus additional information at the end of the reference indicating the location of the material.
Here is an example of entire book. For other eBook variations, such as a book chapter or edited book, follow the format for the print version and just add the URL and accessed date at the end:
Kolt GS, Andersen MB. Psychology in the Physical and Manual Therapies. Edinburgh, Scotland: Churchill Livingstone; 2004. http://www.netLibrary.com/urlapi.asp?action=summary&v=1&bookid=79424. Accessed September 24, 2012.
Authors: Kolt GS, Andersen MB.
Last name first and then abbreviate first and middle names to just the first initial with no spaces, commas, or periods in between. Place a comma between multiple authors. If there are more than six authors listed, list the first three authors followed by et al.. End with a period.
Title & subtitle of the book: Psychology in the Physical and Manual Therapies.
The title & subtitle, if any, are separated by a colon. Capitalize all major words of the title and subtitle. Italicize the title. End with a period.
Volume number and volume title (if applicable): N/A
Give volume number preceded by Vol with no period. End with a period. Ex = Vol 3. See section 3.12.6 if there is a separate volume title.
Edition number (if applicable): N/A
Do not indicate a first edition. Give edition number in ordinal format such as 2nd, 3rd and so on followed by ed. End with a period. Example: 6th ed.
Publisher: Churchill Livingstone;
Use the full name of the publisher from the book's title page but format & abbreviate it per the rules in section 3.12.9 & 14.7. End with a semi-colon.
Year of Publication: 2004.
List the year of publication, which appears on the title page or the title page verso (back side of title page). End with a period.
Give the web address for the eBook followed by a period.
Date of access: Accessed September 24, 2012.
Date you accessed (viewed) the page preceded by the word Accessed. End citation with a period.