Johns Hopkins Guide to Literary Theory & Criticism: Extensive essays on major critics, movements, and schools of thought.
Literary Reference Center: Includes author biographies, criticism, plot summaries and book reviews.
Literature Resource Center: Similar to Literary Reference Center. Contains several major biographical dictionaries, including The Dictionary of Literary Biography, Contemporary Authors, and the Twayne's Author Series.
The Literary Encyclopedia: A growing list of entries on authors, literary works, and related historical events. The authors covered either write in English or have been translated into English.