Online library services may be down Saturday February 22
OED : Oxford English Dictionary
The full text of the 20-volume 2nd edition (1989) plus regular updates.
Oxford Dictionary of National Biography
Biographies of people of distinction in the British Isles and its colonies, from the 4th century to the 21st.
Johns Hopkins Guide to Literary Theory & Criticism
Full-text encyclopedia with entries for critics, theorists, schools and movements.
Stanford encyclopedia of philosophy
Refereed dynamic open-access online encyclopedia from Stanford University. Updated continuously.