Planetmath

Planetmath is a collaborative online mathematical encyclopedia and reference resource, located here. Its content was earlier licensed under the GNU Free Documentation License, but it moved to a Create Commons Attribution-Share Alike license (CC-by-SA). It runs on Noosphere and its entries are written in LaTeX. It was started in 2000 and was an attempt to replace Mathworld, which had been taken down because of a lawsuit by CRC Press.

General information within Planetmath/officially linked to from Planetmath:

• The Planetmath thesis by Aaron Krowne, one of the founders of Planetmath.

External information on Planetmath:

• Wikipedia entry about Planetmath.

My blog posts mentioning/referencing Planetmath:

• Wikipedia — side effects (November 16, 2008).

• Can the Internet destroy the University? (29 January, 2009)

• Math websites falling into disuse? (October 31, 2009)

• Planetmath and Mathworld losing out to Wikipedia (May 28, 2010)

Other magazine articles and blog entries mentioning Planetmath:

• Motivation and value of free resources: Wikipedia and Planetmath show the way (16 February 2005) by Aaron Klemm in the Free Software Magazine.

• Quick note about Planetmath (June 11, 2006) by Mostly Mathematics (Daniel McLaury).