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Perfect Graphs - http://www.aimath.org/WWN/perfectgraph/
Conjectures and open problems, maintained at the AIM. |
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Graph Theory Open Problems - http://dimacs.rutgers.edu/~hochberg/undopen/graphtheory/graphtheory.html
Six problems suitable for undergraduate research projects. |
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Past Open Problems Columns - http://www.math.uiuc.edu/~west/pcol/pcolink.html
By Douglas B. West, from the SIAM Activity Group Newsletter in Discrete Mathematics. |
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Problems in Graph Theory - http://www.maths.qmw.ac.uk/~pjc/oldprob.html
Maintained by Peter Cameron. |
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Problems in Signed, Gain, and Biased Graphs - http://www.math.binghamton.edu/zaslav/Bsg/sgbgprobs.html
Compiled by Thomas Zaslavsky. |