Radioactivity teaching: environmental consequences of the radiological accident in Goiânia (Brazil) - Anjos, R. M.; Facure, A; Lima, E. L. N.; Gomes, P. R. S.; Santos, M. S.; Brage, J. A.; Okuno, Emico; Yoshimura, Elisabeth Mateus; Umisedo, Nancy Kuniko (American Journal of Physics, 2001)