Hi abraham,
When you tranfer a Contract or Scheduling Agreement or Purchasing Inforecord master in R/3 (or ECC any version) then TPSRC is the program used to create External Procurement Relationships (txn /SAPAPO/PWBSRC1) in APO during CIF transfer. Dont forget that you also create a Transportation Lane (txn /SAPAPO/SCC_TL1) to reflect that relationship.
Regards!