Answer:

"Epidemiology of Substance Abuse." Source Book of Substance Abuse and Addiction. Ed. Langhorne LS, et al. Baltimore, MD: Williams &Wilkins, 1996: 23-216.

Commentary:

First of all, capitalize all important words in the title of the article and the title of the book.

Secondly, move the title of the book after the article title.Italicize the name of a book.

Thirdly, use "Ed." to indicate that the following person is the editor of the book.

Fourthly, Maryland should be abbreviated using both "M" and "D" in capital letters.

Finally, use a colon after the place of publication.

Note: The way the writer has proposed this entry one must assume that the article is unauthored. However, it seems unlikely that credit would not be given to an author or authors (especially if the article ran from page 23-216 as the writer suggests at the end.

Second Note: It is unlikely that in an edited collection of articles (presumably all of them unauthored) one of these articles would run from page 23-216.