SAP ABAP Table ISU2A_BILL_DOC (Billing document (internal)) is using

• Table (3)

#	Object Type	Object Name	Object Description	Note
1	Table	ERCH	Billing Doc. Data
2	Table	ERCH_JBP	Special ERCH Fields for JBP (Japanese Billing Period)
3	Table	ISU_ADMIN	Creation and Change Data (Author, Group and Deletion Flag)