是一本很好用的有关c#的书来的，还跟通信有关的，电子通信方面的同学应该很有用-Is a good used books to the c#, and even went to communications-related, electronic communications should be useful for students

机械设计类书籍，关于轴承、齿轮、带轮等的设计方法及注意事项-Mechanical design books, on the bearings, gears, pulleys and other design methods and precautions