TY  - BOOK
AU  - Erich Gamma, richard Helm, Ralph Johnson, John Vlissides
TI  - Design Patterns: Elements of Reusable Object-Oriented Soft
SN  - 9781282608658
CY  - Pearson
UR  - https://ebooks.elibrary.in.pearson.com/wr/launchbook.html?id=12032024
ER  -