1. Albert RE (1976) Skin carcinogenesis. In: Andrade R, Gumport SL, Popkin GL, Rees TD (eds) Cancer of the skin. Saunders, Philadelphia London Toronto, p 111
2. Auerbach H (1961) Geographic variation in incidence of skin cancer in the United States. Public Health Rep 76: 345
3. Bean SF, Foxley EG, Fusaro RM (1968) Palmar keratoses and international malignancy. A negative study. Arch Dermatol 97: 528
4. Belisario IC (1959) Cancer of the skin. Butterworth, London
5. Berenblum I (1964) The two-stage mechanism of carcinogenesis as an analytical tool. In: Emmelot P, Muhlbock O (eds) Cellular control mechanisms and cancers. Elsevier, Amsterdam