In A1.3 The Expressive Power of Nand
There is a phrase:
"It follows that any Boolean function can be represented by a Boolean expression containing only And, Or, and And operators."
![](http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/file/n4036134/a-1-3-the-expressive-power-of-nand.jpg)
I think this was supposed to be "... only And, Or, and
Not operators."