TY  - BOOK
AU  - Erich Gamma, richard Heln, Ralph Johnoon, Johm visside
AU  - Erich Gamma, richard Heln, Ralph Johnoon, Johm visside
TI  - Design Patterns Elements of Reusable Object Oriented Software
PY  - 1999///
CY  -  India
PB  - Addison-Wesley
ER  -