The 90-minute day studies examined how sleep and sleepiness evolve in people living on this very unusual schedule. Much was learned about the regulation of sleep from these and other similar studies in other labs.

Carskadon, M.A. and Dement, W.C. Sleep studies on a 90-minute day. Electroencephalogr. Clin. Neurophysiol. 39: 145-155, 1975.

Carskadon, M.A. and Dement, W.C. Sleepiness and sleep state on a 90-minute schedule. Psychophysiology 14: 127-133, 1977.

Carskadon, M.A. and Dement, W.C. Distribution of REM sleep on a 90-minute sleep-wake schedule. Sleep 2: 309-317, 1980.