Proof when attesting witness denies execution. 70. If the attesting witness denies or does not recollect the execution of the document, its execution may be proved by other evidence.

Admission of execution by party to attested document. 69. The admission of a party to an attested document of its execution by himself shall be sufficient proof of its execution as against him, though it be a document required by law to be attested.

Proof where no attesting witness found. 68. If no such attesting witness can be found, it must be proved that the attestation of one attesting witness at least is in his handwriting, and that the signature of the person executing the document is in the handwriting of that person.