TY  - BOOK
ED  - World Intellectual Property Organization
TI  - International Patent Classification 1979: Vol. 1-8, Guide
PY  - 1979///
CY  - München [u.a.]: 
PB  - Heymann, 
KW  - Internationale Patentklassifikation
N1  - 15.555-15.556
ER  -