A good link about GAMS learning: http://yetanothermathprogrammingconsultant.blogspot.com/

Transportation journals: http://web.pdx.edu/~bertini/journals.html

Global optimization test problems: http://solon.cma.univie.ac.at/glopt/test.html

P versus NP problems: http://www.win.tue.nl/~gwoegi/P-versus-NP.htm

Glossary of supply chain: http://www.inboundlogistics.com/cms/logistics-glossary/

The VRP Web and instances: http://www.bernabe.dorronsoro.es/vrp/