ABCD Matrix of transmission lines connected in cascade

Hello,

I need verification of problem which I analyzed yersterday. Let we say, that we have simple circuit composed of transmission lines:

As you can see, we have one simple quarter-wave TL, and two open-ended stubs at the end. I want to derive an ABCD matrix of entire circuit in electrical length domain (by using such matrix I want to draw S11 characterisitic from well known transformation equations: ABCD-> S). So I try to make such operation:
[ABCD ALL] = [ABCD TL] [ABCD STUB 1] [ABCD STUB 2]

However I'm not sure whether this is proper idea. Could you confirm such method ?

Regards,
E.

Wrong.

Evaluate Yin_stub1 and Yin_stub2.
Yin_stub = Yin_stub1 + Yin_stub2

Zin = (A/Yin_stub + B) / (C/Yin_stub + D)
Here {A, B, C, D} is for transimission line of Z1.