Lookup via transfer rule
I want to write from two DSO's to an InfoCube. One DSO contains Sales data and the other Customer data. In case of a matching key in mentioned DSO's customer data must be written to the InfoCube. So therefor i need to do a customer lookup. This key contains ZRBDOCNR and ZRBPOSNR. Customer InfoObject = ZRBCUS. My question is: "how do i realize this in ABAP code?"
Thanks in advance!