2[7]Bruce L Golden. An adaptive memory heuristic for a class of vehicle routing problems with minmax objective [J].Computers&Operations Research, 1997, 24 (5): 445 -452.
3[8]Jacques Renaud. A tabu search heuristic for the multidepot vehicle outing problem [J]. Computers&Operations Research, 1996, 23 (3): 229 - 235.