SAP PASS BY REFERENCE GLOSRY documentation, setup help and example usage

ARTICLE

pass by reference
Method of passing data from actual parameters to formal parameters when the proecdure is called. It is defined in the parameter interface of a procedure . In pass by reference, no local data object is specified for the actual parameter. Instead, the procedure receives a reference to the actual parameter during the call, and works with the actual parameter itself. Input parameters that have been passed by reference are not allowed to be changed in the procedure. Also see pass by reference .
ABAP_MORE_INFO