We also have a collection of eBooks available for you to search, you can try browsing in the "Engineering & Technology" and "Sciences" categories when you do so:
Formerly NetLibrary, eBook Collection contains over 20,000 public-domain titles.
Access Tip: Also available via 
MeL.org
Superstrings and Other Things by 
A Graphical Approach to College Algebra by 
A First Course in Differential Equations with Modeling Applications by 
Elements by 
CRC Handbook of Chemistry and Physics 87th Edition by 
The History and Use of Our Earth's Chemical Elements by 
McGraw-Hill Encyclopedia of Science and Technology Volumes 1-20 11th Edition by 
The Princeton Companion to Mathematics by 
