Osmania University Books
https://www.osmania.ac.in/e-books.php
National Digital Library
NCERT E -Books
https://ncert.nic.in/ebooks.php?ln=
Swayam Prabha
https://www.swayamprabha.gov.in/
T-SAT
E-Library Telangana
https://elibrarytelangana.blogspot.com/