History of classification of patents
Bailey, M F
History of classification of patents - U.S.A.: The Journal of the patent office society, 1946 - 84p.
Classification patents
Library history Library management
D 025.4:608.3(091) / H6
History of classification of patents - U.S.A.: The Journal of the patent office society, 1946 - 84p.
Classification patents
Library history Library management
D 025.4:608.3(091) / H6