These resources provide quick references to information on a variety of topics including literature.
Oxford Reference Online Premium
This online collection includes 130+ subject dictionaries and the Oxford World Encyclopedia, bilingual dictionaries, timelines, 12,000 images and 500+ color maps.
The OED is the accepted authority on the evolution of the English language over the last millennium. It is a guide to the meaning, history, and pronunciation of over half a million words, both present and past.