Code of Federal Regulations Title 33. Navigation and Navigable Waters § 33.125.23 United States citizens

(a) Birth certificate or certified copy thereof.

(b) Certificate of naturalization. This shall be presented by all persons claiming citizenship through naturalization.

(c) Baptismal certificate or parish record recorded within one year after birth.

(d) Statement of a practicing physician certifying that he attended the birth and that he has a record in his possession showing the date and place of birth.

(e) United States passport.

(f) A commission in one of the armed forces of the United States, either regular or reserve;  or satisfactory documentary evidence of having been commissioned in one of the armed forces subsequent to January 1, 1936, provided such commission or evidence shows the holder to be a citizen.

(g) A continuous discharge book, or Merchant Mariner's Document issued by the Coast Guard which shows the holder to be a citizen of the United States.

(h) If an applicant claiming to be a citizen of the United States submits a delayed certificate of birth issued under a State's seal, it may be accepted as prima facie evidence of citizenship if no one of the requirements in paragraphs (a) through (g) of this section can be met by the applicant and in the absence of any collateral facts indicating fraud in its procurement.

(i) If no one of the requirements in paragraphs (a) through (h) of this section can be met by the applicant, he should make a statement to that effect, and in an attempt to establish citizenship, he may submit for consideration data of the following character: