Collection
Directory of Open Access Books
1,591
Springer Book Archives -2004
690
Springer eBooks 2005-
621
Eighteenth Century Collections Online / ECCO
345
National Center for Biotechnology Information
190
OAPEN
27
Springer Protocols Archive 1981-2004
9
Mohr Siebeck eBooks
7
Cambridge Books Online
2
ACS Symposium Series
1
DeGruyter MPG Collection
1
Editoria Italiana Online
1
O'Reilly
1
Wiley Online Books
1