TY  - BOOK
AU  - Gupta, Prem Kumar
AU  - Hira, D S
TI  - Problems in operations research: principles and solutions 
SN  - 9788121909686
U1  - 658.4034 
PY  - 1991///
CY  - New Delhi
PB  - S. Chand and Company Limited
KW  - Operations research
ER  -