Peng Tao，H. Bernhard Schlegel. QM/MM Study Tutorial using GaussView, Gaussian, and TAO package.
3, 以AMBER12为接口: Hybrid QM/MM计算
This tutorial explains how to set up QM/MM simulation using AMBER 12 and Gaussian (g03 or g09) which includes cutting a covalent bond between the QM and MM parts.
4, Gaussian 09 Windows入门教程
This is a quick tutorial that will help you to make your way through the first steps of computational chemistry using Gaussian 09W software (G09). The tutorial is oriented to beginners and describes in detail the most used calculations done using G09. However, the theoretical basis of these cal- culations will not be covered here. If you are interested in understading the details, please refer to textbooks targeting this subject. I found  and  very helpful, and strongly recommend to take a look at these wonderful books.