(a) Reference to other tariffs prohibited except as authorized. A tariff shall not refer to nor provide that it is governed by any other tariff, document, or publication, or any part thereof, except as specifically authorized by this part.
(b) Reference by fare tariff to governing tariffs. A fare tariff may be made subject to a governing tariff or governing tariffs authorized by this subpart: Provided, that reference to such governing tariffs is published in the fare tariff in the manner required by § 221.20(h).
(c) Participation in governing tariffs. A fare tariff may refer to a separate governing tariff authorized by this subpart only when all carriers participating in such fare tariff are also shown as participating carriers in the governing tariff: Provided, that:
(1) If such reference to a separate governing tariff does not apply for account of all participating carriers and is restricted to apply only in connection with local or joint fares applying over routes consisting of only particular carriers, only the carriers for whom such reference is published are required to be shown as participating carriers in the governing tariff to which such qualified reference is made.
(2) [Reserved]
(d) Maximum number of governing tariffs. A single fare tariff shall not make reference to conflicting governing tariffs.