TY  - BOOK
AU  - Gamma,Erich   .
AU  - Helm,Richard  .
AU  - Johnson,Ralph  .
TI  - Design patterns elements of reusable object-oriented software / 
U1  - 005.117 
PY  - 1995///
CY  - New Delhi : 
PB  - Pearson Education , 
KW  - Object - oriented programming
KW  - Object-oriented software
ER  -