(and Mathematics in general)

This is my old link list for Geometry. It is no longer systematically updated, as I am not doing geometry anymore. Nowadays you can find me on the MathLinks (Art of Problem Solving) forum (mostly in the Olympiad Section and the College Playground), on MathOverflow, and occasionally on the Matheplanet (German).

English pages

• http://www.imomath.com/
The IMO Compendium: A project to collect the problems of past IMO Shortlists and various other mathematical olympiads from all over the world. The site contains a lot of interesting materials.

• http://www.unl.edu/amc/a-activities/a4-for-students/s-index.shtml
AMC's Student Corner: Resources helpful for students preparing to mathematical olympiads. Among them, the 1996-97 and 1997-98 issues of "Olympiad problems from around the world"; needless to say, these contain some geometry problems too.

• http://www.ajorza.org
Andrei Jorza's Mathematical Olympiad Archive: Problems and solutions of various mathematical olympiads. (And some notes on algebra.)

• http://www.cpohoata.com/
Cosmin Pohoata: Some notes on Euclidean/triangle geometry.

German pages

• http://www.emis.de/MATH/JFM/
Jahrbuch über die Fortschritte der Mathematik: Freely accessible reviews of mathematical papers published until 1942.

• http://math4u.de/
Math4u: Eckard Specht's online problem collection (with solutions; each problem in GIF, PS and PDF formats). Good reference for elementary triangle geometry.

• http://dynageo.de/
Euklid DynaGeo: A quite powerful program for dynamical geometry with the computer. The newer versions (2.5-) create animated drawings

• http://www.uni-duisburg.de/SCHULEN/STG/jufopage/indexjufo.html (offline)
Jugend forscht at Duisburg
: Some works for the "jugend forscht" competition, including Triangle Geometry.

• http://www.bundeswettbewerb-mathematik.de/
Bundeswettbewerb Mathematik: The German National Mathematics Competition (former FRG olympiad). Some of the problems are on geometry. The page http://www.bundeswettbewerb-mathematik.de/imo/aufgaben/aufgaben.htm contains the problems and solutions of the recent German IMO team selection tests.

Dutch pages

French pages

Russian pages

• http://www.mccme.ru/mmmf-lectures/books/
Biblioteka "Matematicheskoe prosveshjenie": Booklets based on lectures for school students. See, for example, Prasolov's handout on isogonal conjugation.

Geometricheskie zadachi: A collection of geometrical problems with solutions (including some advanced results of Triangle Geometry). Certain dynamic Java applets.

• http://kvant.mccme.ru/
Kvant: A Russian/Soviet journal for Elementary Mathematics founded in 1970. Several old issues are archived in GIF format.

• http://plm.mccme.ru/
Populjarnye lekzii po matematike: Downloadable scans of a really famous series of booklets on elementary mathematics.

• http://www.allmath.ru/
Allmath.ru: Collection of books on school and university mathematics, downloadble in DjVU format.

• http://www.math.ru/

• http://math.ras.ru/

• http://sci-lib.com/subject.php?subject=1
Boljshaja nauchnaja biblioteka: Another open DjVU book collection.

Internet Libraries

A grossly underestimated source of mathematical texts. You can find works of Newton, Gauss, Cayley and hundreds of other historical authors - but also newer textbooks and thousands of books you have never heard of before. I have given up sorting these links into the above language categories since many libraries contain works in very different languages - e. g. some French libraries containing German texts.

• http://www.archive.org
Internet Archive: Besides the famous wayback machine that stores and makes accessible older versions of websites, this ressource contains a number of historical books.