TY  - BOOK
AU  - Usher, Abbott Payson
TI  - A History of mechanical inventions: Abbott Payson Usher
U1  - 620.009 
PY  - 1954///
CY  - Cambridge Mass
PB  - Harvard University Press
KW  - Technical engineering - History
N1  - Bibiography: P.433-443
ER  -