Comparison between an African town and a neighbouring village shows delayed, but not decreased, sleep during the early stages of urbanisation

A.D. Beale, M. Pedrazzoli, B.D.S.B. Gonçalves, F. Beijamini, N.E. Duarte, K.J. Egan, K.L. Knutson, M.V. Schantz, L.C. Roden