The Cambridge Companions series includes hundreds of titles on philosophy. The subjects are quite diverse, providing researchers with solid background information and analysis on philosophers, philosophy and history, landmark texts, and philosophical concepts.

JSTOR is an interdisciplinary archive including articles, book reviews, and eBooks

Oxford Bibliographies offer authoritative research guides on a variety of topics. The bibliographies include overviews of the subject and annotated references to important books and articles.

Oxford Handbooks in Philosophy feature articles written by scholars on a wide variety of topics.

Oxford Scholarly Editions Online (OSEO) provides searchable, full-text access to Oxford scholarly editions in English, Classical Studies,and Philosophy. The editions include annotations, and are useful for instruction and scholarship. Philosophical works in the OSEO include Hegel's Philosophy of Mind, Philosophy of Right, and Philosophy of Nature; Leibniz's Logical Papers & New System and Associated Contemporary Texts; The Clarendon Edition of the Works of Thomas Hobbes; and Schopenhauer's Parerga and Paralipomena: Short Philosophical Essays.

Philosopher's Index is a scholarly database containing over 650,000 records for philosophical research dating back to 1902. Full-text links are included when access is available.

Project Muse focuses on the Humanities and Social Sciences and includes more current content, including access to eBooks.