National Library of Medicine (U.S.) National Library of Medicine (U.S.) NIM audiovisuals catalogs. (1991). National Library of Medicine audiovisual catalog: Annual cumulation 1991. U.S. Dept. of Health and Human Services, National Library of Medicine.
Chicago-viite (17. p.)National Library of Medicine (U.S.) National Library of Medicine (U.S.) NIM audiovisuals catalogs. National Library of Medicine Audiovisual Catalog: Annual Cumulation 1991. Bethesda, MD: U.S. Dept. of Health and Human Services, National Library of Medicine, 1991.
MLA-viite (9. p.)National Library of Medicine (U.S.) National Library of Medicine (U.S.) NIM audiovisuals catalogs. National Library of Medicine Audiovisual Catalog: Annual Cumulation 1991. U.S. Dept. of Health and Human Services, National Library of Medicine, 1991.