Sobreiro BP, Lucon AM, Pasqualotto FF, Hallak J, Athayde KS, Arap S. Semen analysis in fertile patients undergoing vasectomy: reference values and variations according to age, length of sexual abstinence, seasonality, smoking habits and caffeine intake. Sao Paulo Med J [Internet]. 2005 Jul. 7 [cited 2025 Mar. 12];123(4):161-6. Available from: https://periodicosapm.emnuvens.com.br/spmj/article/view/2345