It is correct. Homo is a genus of great apes. It emerged around 2.4 million years ago. And it does include modern humans (Homo Sapiens).

I'm not sure which part you're taking issue with?

> Normally one doesn't refer to one genus as being part of another genus.

That's right. Australopithecus and Homo are different genera.

> between apes and humans

Not sure what you're saying here. Humans and Australopithecines are both apes.