Upon completing the examination for said liens, the clerk shall enter upon the tax sale book upon the page showing the sale a notation to the effect that such examination had been made, giving the names and addresses, if known, of said lienors, the book and page where the liens are created, and the date of mailing by registered mail the notice to the lienors. If the clerk finds no liens of record, he shall so certify on said tax sale book. In each instance the clerk shall date the certificate and sign his name thereto.