Commissioner’s certificates
40.—(1)  When the Commissioner has ascertained the amount of the duty and interest payable on an estate duty affidavit or account, he shall certify the same in writing on the affidavit or account, as the case may be.
(2)  When the amount payable on an estate duty affidavit or account has been paid, the Commissioner shall certify such payment in writing on the affidavit or account, as the case may be.
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