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3. A Canadian Study of Smoking and Health;Best,1966
4. Inhalation of tobacco smoke by pipe and cigar smokers;Castleden;Lancet,1977
5. The Relationship of Smoking and Some Social Covariables to Mortality and Cancer Morbidity. A Ten-year Follow-up in a Probability Sample of 55,000 Subjects, Ages 18–69;Cederlof,1975