A petition for leave to appeal from the judgment, decree or order of an Administrative Court or Service Tribunal shall specify succinctly in separate paragraphs, the substantial questions of law of public importance upon which leave is sought and, in other respects, the provisions of Order XIII or Xxi of these Rules shall apply mutatis mutandis to such petition or appeal, as the case may, except that no security for costs shall be required to be deposited and no Court-fee, Process Fee, Search Fee or Copying Fee shall be charged.