(a) the execution and delivery to the donee of a signed statement, or
(b) an oral statement of revocation made in the presence of two persons, communicated to the donee, or
(c) a statement during a terminal illness or injury addressed to an attending physician and communicated to the donee, or
(d) a signed card or document, found on his person or in his effects. 2. Any document of gift which has not been delivered to the donee may be revoked in the manner set out in subdivision one of this section or by destruction, cancellation, or mutilation of the document and all executed copies thereof. 3. Any gift made by a will may be revoked or amended in the manner provided for revocation or amendment of wills or as provided in subdivision one of this section.