Can I refer to a dependent claim, to a word that is in the claim that the dependent claim depends on?

Question

For example:

1. It is a system comprising X, Y, Z
2. The system of claim 1, wherein X is W
3. The system of claim 2, wherein Z is P connected to W

In the claim 3, I need to refer to both Z (which is in the claim 1 and I expect it is in the claim 2) and W which is in the claim 2.

Answer 1

Yes.

A dependent claim contains all the limitations of the claims from which it depends, whether directly or indirectly. Thus, claim 2 includes all the limitations of claim 1, and claim 3 includes all the limitations of claims 1 and 2.

Your claim 3 has antecedent basis for referring to elements W, Y, and Z without having to reintroduce them.