April 27, 2015 from http://www.theorsociety.com/Pages/ORMethods/Heuristics/articles/HistoryTSP.aspx
Frontline Systems. (n.d.) Downloaded on January 2, 2015 from http://www.solver.com/
Patterson, M. & Harmel, B. (2003). Solving the Traveling Salesman Problem Using Premium Solver Platform. International Journal of Management , 22 (4), 532-541.
Robinson, J. B. (1949). On the Hamiltonian Game (a traveling salesman problem). Rand Research Memorandum RM-303.
Tuza, Z. (2001). Unsolved Combinatorial Problems, Part I. Downloaded on December 30, 2015