See this example properly formatted in the QUT Cite tool.
Standard in-text citation examples are in Getting started - In-text citation.
Author AA, Author BB. Title. Edition. Place of publication: Publisher; Year. Title of entry; page number.
[20] Christensen AJ, Martin R, Morrison Smyth J. Encyclopedia of health psychology. New York: Kluwer Academic/Plenum Publishers; c2004. Relapse Prevention; p.245.
Author AA, Author BB. Title [Internet]. Edition. Place of publication: Publisher; Year of publication. Title of entry; [cited Year Month Day]; [# of pages/paragraphs/screens]. Available from: http://www.xxxx.xx.xx
[4] Mosby's Medical Dictionary [Internet]. 10th ed. St Louis (MO): Elsevier; 2017. Galactosemia; [cited 2017 Dec 17]; [about 2 paragraphs]. Available from: https://ebookcentral.proquest.com/lib/qut/detail.action? docID=4747147
If there is no author, use the title of the work and list the title of the entry at the end of the reference.
For entries without page numbers, include the total number of screens, paragraphs or lines, whichever is most practical. Precede with about and place it in square brackets, e.g. [about 7 screens].