evidence: - If the mother is married to the father either at the time of conception or at the time of birth, then the last name of the mother's husband will be entered, unless paternity has been determined otherwise by a court of competent jurisdiction. - If the mother is not married to the father either at the time of conception or at the time of birth, then the name of the father will be entered only if he and the mother have signed a written consent. [...] In all other cases, the last name of the child will be the legal last name of the mother at the time of birth as designated by the mother. The parents may designate a last name that is not the legal last name of the mother or father, if that last name is chosen in accordance with a legitimate cultural naming practiced in the nation of origin of one or both parents.