López MV, Rivero E, Serra C, Campo M, Raurich M, Bonfill X. Health survey in health care professionals in Barcelona. Arch Prev Riesgos Laborales. 1998;1(2):55-62.
Cann CI, Fried MP, Rothman KJ. Epidemiology of squamous-cell cancer of the head and neck. Otolaryngol Clin N Am. 1985 Aug 1;18(3):367-88.
Suit HD, Sedlacek R, Fagundes L, Goitein M, Rothman KJ. Time distribution of recurrences of an immunogenic and non-immunogenic tumor following local irradiation. Radiat Res. 1978 Feb;73(2):251-66.