1<?xml version="1.0" encoding="utf-8" ?> 2<book> 3 <title>Design Patterns</title> 4 <author>Erich Gamma</author> 5 <author>Richard Helm</author> 6 <author>Ralph Johnson</author> 7 <author>John Vlissides</author> 8</book><book> 9 <title>Pattern Hatching</title> 10 <author>John Vlissides</author> 11</book>