e-boook

• IEEE EXPLO Digital Library

                        http://ieeexplore.ieee.org/Xplore/home.jsp

• Questia

                        https://www.questia.com/library

• DOAB– Directory of Open access Book 

                        http://www.doabooks.org/

• The Online Books Page

                       http://onlinebooks.library.upenn.edu/

• E-Book Directory

                      http://e-booksdirectory.com