van Hasselt, S. J., Rusche, M., Vyssotski, A. L., Verhulst, S., Rattenborg, N. C., & Meerlo, P. (2020). The European starling (Sturnus vulgaris) shows signs of NREM sleep homeostasis but has very little REM sleep and no REM sleep homeostasis. Sleep, 43(6): zsz311. doi:10.1093/sleep/zsz311.