TY  - BOOK
TI  - Official Catchword index to the International Classification of Patents
PY  - 1969///
CY  - Kent: 
PB  - Morgan-Grampian Books, 
KW  - Internationale Patentklassifikation
KW  - Stichwortindex
KW  - Englisch
N1  - 14.312
ER  -