Collection
Springer Book Archives -2004
415
Springer eBooks 2005-
274
Directory of Open Access Books
78
OAPEN
16
Digi20
14
Oxford University Press
13
MIT Press eBook Archive
9
Oxford Handbook Online
6
DeGruyter MPG Collection
4
Editoria Italiana Online
3
JSTOR Open Access Books
3
Cambridge Books Online
2
O'Reilly
1