Collection
Springer eBooks 2005-
253
Springer Book Archives -2004
143
Directory of Open Access Books
96
Karger eBooks Collection 1997-2013
58
National Center for Biotechnology Information
35
World Bank E-Library Archive
7
OAPEN
3
Elsevier ScienceDirect eBooks
2
JSTOR Open Access Books
2
O'Reilly
2
Wiley Online Books
1