Dictionaries & Encyclopedias
Oxford Reference Online
Includes The Concise Oxford Dictionary of Mathematics, 2nd edition, which covers everything from pure & applied mathematics and statistics, as well as topics of more general interest such as fractals, game theory and chaos.
Encyclopaedia of mathematics
Available in the Taylor Library reference collection at QA5.M3713 1988.
A comprehensive and interactive online encyclopedia of mathematics. Most entries include references.