title: How old is the immunodeficiency virus?
authors: Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany.
authors: M
authors: M
authors: Eigen
authors: K
authors: K
authors: Nieselt-Struwe
mesh_terms: D000818:Animals; D005075:Biological Evolution; D014644:Genetic Variation; D006678:HIV / Q000235:genetics; D015658:HIV Infections / Q000382:microbiology*; D006801:Humans