how to trace the production order in the TR with requirement type P

Dear all,

a little bit of background of myself and my R/3 setup for the following questions:

We are using WM-PP interface, which means we uses production supply and control circle in the setup.

I am not a PP person and am quite new in WM-PP area.

Questions:

1 - In which table I am able to trace back the production order (i.e. source) of a transfer requirement as the at the TR header which is having a requirement type (BETYP) of P, BUT having a requirement number(BENUM) which IS NOT a production order but the cost center