When either party is a minor, no license shall be granted without the written consent under oath of: (1) Either one of the parents of such minor, if the parents are living together; (2) the parent having the legal custody of such minor, if the parents are living separate and apart from each other; (3) the surviving parent, if one of the parents of such minor is deceased; or (4) the guardian, conservator, or person under whose care and government such minor may be, if both parents of such minor are deceased or if such guardian, conservator, or person has the legal and actual custody of such minor. The county clerk shall be justified in issuing the license, without further proof, upon receiving an affidavit setting forth the facts with reference to the conditions above specified and giving consent to the marriage, signed by the person authorized to give written consent under such circumstances.