Sleep duration of adolescents who work and don't work and consequences to some of their activities: education and work - Teixeira, L. R.; Fischer, Frida Marina; Latorre, Maria do Rosário Dias de Oliveira; Martins, Ignez Salas; Oliveira, Denise Cristina de; Costa, L. A. R.; Perestrelo, J. P. P.; Marinho, S. P.; Cooper, S. (Latin American Symposium of Chronobiology, 2001)