TY  - BOOK
AU  - Gupta, Prem Kumar
AU  - Hira , D. S.
TI  - Problems in operations research: Principles and solutions 
SN  - 8121909686
PY  - 1991///,2003 re.p
CY  - New Delhi
PB  - S Chand
KW  - Operations Research
ER  -