TY  - BOOK
AU  - Graf,Rudolf F.
AU  - Whalen,George J.
TI  - How it works, illustrated: everyday devices and mechanisms
SN  - 0060115890
AV  - TX298 .G68
U1  - 620 
PY  - 1974///]
CY  - New York
PB  - Popular science
KW  - Technology
KW  - Popular works
KW  - Local
N1  - 921004
ER  -