Some of the details and tips in this book are collected from the Internet, some ones are found by myself. I will try to list the source of a detail if it is possible. But I'm sorry that it is impossible task to do this for every detail.
Thanks to Olexandr Shalakhin for the permission to use one of the wonderful gopher icon designs in the cover image. And thanks to Renee French for designing the lovely gopher cartoon character.
Thanks to the authors of the following open source software and libraries, which are used in building this book: