TY  - GEN
AU  - Haykin,David Judson
AU  - The Luibrary of Congress
TI  - Subject headings: a practical guide 
U1  - 025.33 21
PY  - 1951///
CY  - Washington, U.S.
PB  - Government Printing Office
KW  - ENCABEZAMIENTOS DE MATERIA
N1  - Cab.portada: The Library of Congress
ER  -