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Kirby's Problem List in Low-Dimensional Topology - http://www.math.berkeley.edu/~kirby/
Problems list in PostScript format. |
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Open Problems in Topology - http://www1.elsevier.com/homepage/sac/opit/toc.htm
Collection includes problems in set theory, continua, algabraic structures, analysis, and dynamics. Page includes glossary of terms. Links are in PDF. |
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Thrackle.org - http://www.thrackle.org/
John Conway's Thrackle Conjecture: a compilation of what is known about the question. |
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The Boise Problem Book - http://math.boisestate.edu/~marion/research/BoiseProblemBook/
Problems in combinatorial set theory and topology, collected by Marion Scheepers. |