Where can I get the example C source code in GNU Make Manual ?

[mkckr0]

I am a newbee programmer from China. Recently I am trying to read the GNU Make Manual. But I cannot find the C souce code. In Chapter 2, there is a text editor program as a example including 8 source file and 3 header file. I cannot find them and follow its instruction to run make to compile them. It's not friendly to the new learner. You should provide a download link at the beginning of the manual. By the way, the manual's version is the newest, Version 4.3.