College & Research Libraries has released "The Case of the Disappearing E-Book: Academic Libraries and Subscription Packages" by Helen Georgas.
Here's an excerpt:
This study begins with a one-year analysis of "disappeared" titles from ebrary's Academic Complete™ collection at Brooklyn College of the City University of New York (CUNY). Were certain subject areas particularly affected? Which publishers were removed? Were the removed titles mainly scholarly, or were they titles published by popular presses? Were the removed monographs older publications, or were recent titles deleted as well?