An improved mouth-piece to prevent environmental contamination during radioaerosol inhalation procedures - Braga, F J H N; Souza, Joseane Fonseca; Trad, Clóvis Simão; Santos, Antonio Carlos; Ghilardi Netto, Thomaz; Elias Júnior, Jorge; Hindie, E; Iazigi, Nassim (Health Physics, 1998)