Dechmann, D. K. N., Wikelski, M., van Noordwijk, H. J., Voigt, C. C., & Voigt-Heucke, S. L. (2013). Metabolic costs of echolocation in a non-foraging context support a role for echolocation. Frontiers in Integrative Physiology, 4:. doi:10.3389/fphys.2013.00066.