Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:In another method loosely inspired from ants, Parunak et al. (2005) and Sauter et al. (2005) have robots search for targets by coordinating their actions through a map containing virtual chemicals (pheromone).
Category: