19(1)Sections 10, 11, 13 to 18, 20, 38 and 40 apply
mutatis mutandis to an application for certification by a council of trade unions, but, before the Board certifies such a council as bargaining agent for the employees of an employer in a bargaining unit, the Board shall satisfy itself that each of the trade unions that is a constituent union of the council has vested appropriate authority in the council to enable it to discharge the responsibilities of a bargaining agent.