Source Code For Earliest Implementations Of C

Dennis Ritchie (aka dnr):

In looking over this material, I have mixed emotions; so much of this stuff is immature and not well-done, and there is an element of embarrassment about displaying it. But at the same time it does capture two moments in a period of creativeness and may have some historical interest.

Given Objective-C is a wrapper around C, worth a look as this is where it all started.