“…Moreover, as previously mentioned, our research is different than the existing mixed fleet applications in that we use different capacity resources inside the vehicle, instead of only one resource type, as in the majority of mixed fleet vehicle routing problems. Finally, most studied GVRP with tank refueling (see, e.g., Erdoğan and Miller-Hooks, 2012;Koç and Karaoglan, 2015;Andelmin and Bartolini, 2017;Yavuz, 2017) use a constant fuel consumption rate. However, in recent studies of the EVRP and the Pollution Routing Problem (PRP), the fuel(energy) consumption rate is not linear and depends on several factors, such as the speed, load,..,etc (see, e.g., Demir et al, 2012Demir et al, , 2014Franceschetti et al, 2017;Androutsopoulos and Zografos, 2017;Toro et al, 2017;Salehi et al, 2017).…”