Update README.md (#132)

Author: rosarp

README.md

@@ -74,6 +74,7 @@ TOC is generated by [markdown-toc](https://github.com/jonschlinkert/markdown-toc
 - [Awesome zig wiki](https://github.com/zigcc/awesome-zig/wiki): Other interesting materials about Zig.
 - [Learning Zig](https://www.openmymind.net/learning_zig/) : This guide aims to make you comfortable with Zig. It assumes prior programming experience, though not in any particular language.
 - [Zig 圣经](https://course.ziglang.cc/) : 简单、快速地学习 Zig.
+- [Introduction to Zig - a project based book](https://pedropark99.github.io/zig-book/) : This is an open book by author `Pedro Duarte Faria` that provides an introduction to the Zig programming language, which is a new general-purpose, and low-level language for building robust and optimal software.
 
 ## Tools