The applicant for a class A, B or D certificate of public convenience and necessity shall have a notice of the hearing on such application published in one newspaper of each county into or through which the proposed service would operate, at least fifteen days before the date of such hearing, such notice to be in the form prescribed by the Commission, and an affidavit of the publisher of such newspaper giving the date of publication of such notice shall be filed with the Commission by the applicant at the beginning of such hearing or prior thereto.