00294nam a2200109Ia 450000500170000000800410001708200140005810000240007224500330009626000470012930000080017620260225050937.0260224s9999||||xx |||||||||||||| ||und||  a621.9 WIL  aWillis J. Potthoff  0aFundamentals of tool design   aIslamabad: National Book Foundation c1962  a492