An “open” book

This document is a free book, free as in “free speech”. You are allowed to read it, share it or adapt it under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License (CC-BY-SA 4.0). Unless otherwise stated, the text, illustrations and layout have been made by Guillaume Savaton.

The source code of this book is available in a public GitHub repository. If you notice a mistake or if you want to suggest improvements, you can do it on the Issues page of the du projet.

A “pay-what-you-want” book

If you find this book useful, you can support my work by paying an amount of your choice using one of the following services:

If you prefer to read this book for free, nobody will blame you . And if you change your mind, feel free to come back to this page and click on one of the links above.

A book that respects your privacy

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This book was made with the Pollen publishing system, by Matthew Butterick.
It uses the following fonts, all under the SIL Open Font License Version 1.1: