International patent classification
International patent classification
/ WIPO
- Geneva: WIPO, 1999
- 7th ed. .
Vol. 9 (Section H: Electricity); ISBN: 92-805-0798-2; 159p.
92-805-0798-2
Library science
Patent classification
D 025.4PATENt N9
Vol. 9 (Section H: Electricity); ISBN: 92-805-0798-2; 159p.
92-805-0798-2
Library science
Patent classification
D 025.4PATENt N9