Journal Collection • Book Collection
JSTOR provides access to more than 12 million academic journal articles, books, and primary sources in 75 disciplines. Users from the Max Planck Society have access to selected archival collections of scholarly journals and more than 3,000 Open Access ebooks. The book selection is continuously extended by single e-book acquisitions by MPG libraries. For the archival collections, JSTOR's agreements with publishers include an updating provision referred to as a "moving wall". The moving wall is a fixed period of time ranging, in most cases, from two to five years, that defines the gap between the most recently published issue and the date of the most recent issues available in JSTOR.