Best Choices:
Credo Reference
Reference library of encyclopedias, dictionaries, thesauri, and books of quotations.
Gale Ebooks (formerly Gale Virtual Reference Library)
Variety of reference books covering arts, biography, business, education, environment, general reference, history, information & publishing, law, library science, literature, medicine, multicultural studies, nation & world, religion, science, social science, and technology.
Also Try:
Weekly reports on issues in the news. Online version of Oxford English Dictionary. Reference entries across Oxford’s dictionaries, companions, and encyclopedias.
CQ Researcher
Oxford English Dictionary
Oxford Reference Online