Time delay spefic matrix in state space form

Hi everybody,

does somebody know how a time delay can be applied to a specific matrix in a state space form? In fact, I would like to create a model as below:

ss((A1+A2),B,C,D)

with a time delay for matrix A2 only. I know that a delay for the whole state space can be model with simply

'OutputDelay',X

at the end, but I do not know how this can be specified individually. Does anybody have an idea how this can be done?

Thank you in advance.

Nicolas