Philosophy

InteLex Corporations Past Masters series encompasses the largest collection of primary source full-text electronic editions in philosophy in the world. The series includes significant collections in the history of political thought and theory, religious studies, education, German studies, sociology, the history and philosophy of science, economics, and classics. InteLex acquires and develops definitive editions of the full corpora of the seminal figures in the history of the human sciences, including published and unpublished works, articles, essays, reviews, and correspondence.
From their website

Regularly updated annotated bibliography addressing themes and topics in Philosophy

Oxford Handbooks in Philosophy bring together the world's leading scholars to discuss the latest thinking in a range of major topics in philosophy. Containing specially-commissioned essays with extensive referencing to further reading, the handbooks offer both thorough introductions to topics in the discipline, and a useful reference resource for scholars and advanced students.

Contains citations and abstracts covering scholarly research in the field of philosophy. Covers all major articles from anthologies and books in English, Spanish, German, Italian, and French as well as 480 journals from 38 countries.

PhilPapers is a comprehensive directory of online philosophy articles and books by academic philosophers. We monitor journals in many areas of philosophy, as well as archives and personal pages. We also accept articles directly from users, who can provide links or upload copies

Dynamic reference work on Philosophy from Metaphysics Research Lab at the Center for the Study of Language and Information (CSLI) at Stanford University.