(1) A document of gift is valid if executed pursuant to any of the following:

    (a) This part.

    (b) The laws of the state or country where it was executed.

    (c) The laws of the state or country where the person making the anatomical gift was domiciled, had a place of residence, or was a national at the time the document of gift was executed.

    (2) If a document of gift is valid under this section, the law of this state governs the interpretation of the document of gift.

    (3) A person may presume that a document of gift or amendment of an anatomical gift is valid unless that person knows that it was not validly executed or was revoked.