Wikipedia, the online encyclopedia, lists 44. PlanetMath is a free, collaborative, online mathematics encyclopedia. Overview in the Encyclopedia of Social Work. According to "The Visual Encyclopedia of Science Fiction", ed. The "Catholic Encyclopedia" (1907) regards this genealogy as spurious. "Concise Routledge Encyclopedia of Philosophy". Citizendium, a competing online encyclopedia, launched publicly. He is the author of the "CRC Concise Encyclopedia of Mathematics". One example is the "Stanford Encyclopedia of Philosophy". According to the "Doosan Encyclopedia", some mythology was incorporated. There was speculation about his identity, for example on Encyclopedia Dramatica. The base data for this article are from "The Water Encyclopedia" (1990). EH.Net Encyclopedia, edited by Robert Whaples. "Political and Historical Encyclopedia of Women", 443. Colin Larkin also gave it four stars in his "Encyclopedia of Popular Music" (2006).