APA Citation

World Intellectual Property Organization. (2006). International patent classification: Core level. Geneva, Switzerland: WIPO.

Chicago Style Citation

World Intellectual Property Organization. International Patent Classification: Core Level. Geneva, Switzerland: WIPO, 2006.

MLA Citation

World Intellectual Property Organization. International Patent Classification: Core Level. Geneva, Switzerland: WIPO, 2006.

Warning: These citations may not always be 100% accurate.