TY  - BOOK
AU  - omar,ahmed
TI  - on the maintance of a system of machines by one repairman / 
T2  - External notes
U1  - 338.9 21
PY  - 1970///
CY  - cairo : 
PB  - the institute of national planning, 
KW  - the maintance
KW  - qrmak
KW  - system of machines
KW  - repairman
ER  -