TY  - BOOK
AU  - Vickery, B.C.
TI  - On retrival system theory / 
AV  - Z 699 .A2V5 1965
PY  - 0000///Butterworths,
CY  - London
PB  - 1965
KW  - Information retrieval
N1  - Includes bibliographical references and index
ER  -