§ 17-4-52

(a) All objections and preliminary determinations made pursuant to sections forty-seven, forty-eight, forty-nine and fifty of this article, and all notices required to be given pursuant to sections forty-seven, forty-eight, forty-nine, fifty and fifty-one of this article, shall be in writing. All such objections and preliminary determinations shall be signed by the person making them, and all such notices shall be signed by the person charged with the duty of giving the notice.(b) Notice of any preliminary determination or objection required or authorized by sections forty-seven, forty-eight, forty-nine or fifty of this article shall be given by causing such notice to be delivered to the owner or owners of the real property affected or by causing a copy thereof to be sent by certified or registered mail to such owner or owners at his or their last-known place of business or residence.