A copy of the notice must be mailed to every person who owns, holds, or has the right of interment in any plot in the cemetery or part affected, whose name appears upon the records of the cemetery. The notice must be addressed to the last-known post-office address of the plot owner as it appears from the records of the cemetery, and if that person’s address does not appear or is not known, then to that person at the city, or city and county, in which the cemetery land is situated. If such persons who own, hold, or have a right of interment in any plot of the cemetery or part affected are unknown or cannot be located, the publication of the notice of declaration of intent to disinter provided for in section 23-21-06 must be deemed to be proper and sufficient notice to such persons.