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.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)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.
Trích dẫn kiểu MLA (xuất bản lần thứ 9)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.