Reference Universe

Stanford Encyclopedia of Philosophy
This is considered to be the most authoritative encyclopedia covering the entire discipline of philosophy.
Britannica Academic Edition
Updated daily. The combination of the Encyclopædia Britannica and Merriam-Webster’s Collegiate Dictionary and Thesaurus, magazines and periodicals, and many other research tools provides a variety of reliable sources.
Oxford Dictionary of the Renaissance - 2003
Provides rich detail on all aspects of the Renaissance in 14th to 17th century Europe. Nearly half the entries are biographical, covering artists, thinkers, statesman, and reformers. A table of European ruling houses and a table showing the dates when cities and countries changed from the Julian to the Gregorian calendar are also included.