http://tags.library.upenn.edu/tag/encyclopedias+math PennTags Feed http://tags.library.upenn.edu/makerecord/url/249 http://tags.library.upenn.edu/makerecord/url/249 Access Science is the online version of the comprehensive Mc-Graw Hill Encyclopedia of Science & Technology. It is fully searchable and provides access to articles, illustrations, definitions and biographies of famous scientists. It is an excellent starting point for scientific research. http://tags.library.upenn.edu/makerecord/voyager/250 http://tags.library.upenn.edu/makerecord/voyager/250 A compendium of mathematical definitions, formulas, tabulations and references.