6In the case of any transfer to which this Schedule applies, a joint certificate by or on behalf of the transferor and the transferee that any property specified in the certificate, or any such interest in or right over any such property as may be so specified, or any right or liability so specified, is by virtue of this Act for the time being vested in such one of them as may be so specified, shall be conclusive evidence for all purposes of that fact; and if on the expiration of one month after a request from either of them for the preparation of such a joint certificate as respects any property, interest, right or liability, they have failed to agree on the terms of the certificate, they shall refer the matter to the Secretary of State and issue the certificate in such terms as he may direct.