Learning Chinese: https://guides.library.duke.edu/c.php?g=289492&p=1933722
Chinese Classics online
MCLC Resource Center This resource center contains, among other things, bibliographies of mostly English-language materials on modern Chinese literature, film, art, and culture and is maintained by Kirk A. Denton and Jeremy Sieg at the Department of East Asian Languages and Literatures, The Ohio State University, in conjunction with the journal Modern Chinese Literature and Culture.
Scripta sinaca from the Academia Sinica in Taiwan provides full text access to 1,185 titles, focusing on primary texts important to traditional Sinology. The Academia Sinica also provides several other databases (though not all open access).
国学 A magnificent website containing a huge amount of Chinese full text primary and secondary sources including whole books; short biographies of several hundred past and present scholars, Buddhists, book collectors, etc.; contents or full text of relevant journals; discussion boards, state of the art reports, etc. etc. Unfortunately no working search engine provided. The people behind are academics from various institutions.