1. Sleep and Performance Research Center, Washington State University, Spokane, WA
2. Department of Mathematical Sciences, University of Montana, Missoula, MT
3. Pulsar Informatics Inc., Philadelphia, PA
4. Centre for Sleep Research, University of South Australia, Adelaide, Australia
5. Unit for Experimental Psychiatry, Division of Sleep and Chronobiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA