“…They can provide an initial solution (Toth and Vigo, 1997;Aldaihani and Dessouky, 2003) for the improvement heuristics, or applied in the instances when hundreds of requests are involved and a solution is needed in seconds (Jaw et al, 1986;Diana and Dessouky, 2004;Luo and Schonfeld, 2007). Improvement heuristics, on the other hand, usually attempt to improve the quality of a solution by a local search procedure involving relocation or exchange of vertices or clients (Toth and Vigo, 1997;Cordeau and Laporte, 2003b;Xiang et al, 2006;Kirchler and Wolfler Calvo, 2013;Paquette et al, 2013). To date, the deterministic annealing algorithm proposed by Braekers et al (2014) has been the best heuristic for the homogeneous and heterogeneous DARP, both in terms of solution quality and computation time.…”