Index to the U.S. patent classification
Subtitle: December 1980
Publisher: U.S. Dept. of Commerce, Patent and Trademark Office; U.S. G.P.O.
Published: 1981
Place of publication: Washington, D.C.
Language: eng
Number of pages: 233
Subjects: Patents; Indexes; Classification
Other titles: Manual of classification. (Index)
Notes: Indexes Manual of classification.