1. Animal behavior and internal drives;Richter;Q Rev Biol,1927
2. Spectral resolution of low-frequency, small-amplitude rhythms in excreted 17-ketosteroids; probable androgen-induced circaseptan desynchronization;Halberg;Acta Endocrinol (Copenh),1965
3. Sleep and wakefulness;Kleitman,1963
4. The nature of dreaming;Kleitman,1961
5. Basic rest-activity cycle—22years later;Kleitman;Sleep,1982