Title from cover.
Imprint varies: Springfield, Va., 1983-198 ; Bethesda, MD, <1990->.
Provides information on sources cited in four MEDLARS files: MEDLINE (including the backfiles), Health Planning & Administration, POPLINE, and: <1994-> BIOTECHSEEK.
Vols. for 1983-19 issued by: National Library of Medicine; <1991-> by: National Library of Medicine, Library Operations.