title: Possible origin of human AIDS.
authors.forename: P K
authors.initials: PK
authors.lastname: Lewin
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000209:etiology / Q000635:transmission*; D000818:Animals; D017977:Deltaretrovirus; D006801:Humans; D012756:Sheep; D014790:Visna-maedi virus