Here we would like to draw your attention to PSA21 transaction code in SAP. As we know it is being used in the SAP CA-JVA (Joint Venture und Production Sharing Accounting in CA) component which is coming under CA module (Cross Application).PSA21 is a transaction code used for Source Assignment to Product in SAP.
It comes under the package GJPSA.
Transaction PSA21 technical data table
|Purpose||Source Assignment to Product|