This book is here to help you get your job done with XML. In general, you may use the markup, stylesheets, and code in this book in your programs and documentation (all available for download in a ZIP archive from http://www.oreilly.com/catalog/xmlhks?most of the hacks assume that these example files are in place in a working directory). You do not need to contact us for permission unless you're reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. However, selling or distributing a CD-ROM of examples from an O'Reilly book does require permission. Answering a question by citing this book and quoting an example does not require permission, but incorporating a significant amount of examples from this book into your product's documentation does require permission.
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