Question no 1965 : Invoice Verification Reference Document

In SAP MM ECC6.0, the following invoice verification entries are possible:

(more than one answers)

(A)   Invoice verification with reference to Contract
(B)   Invoice verification with reference to Scheduling Agreement.
(C)   Invoice verification with reference to Material Document number.
(D)   Invoice verification with reference to Release orders (Purchase Orders) against Contracts.
(E)   Invoice verification with reference to Service Entry Sheet.
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