16 CFR 308.4 – Special rule for infrequent publications
(a) The provider of any pay-per-call service that advertises a pay-per-call service in a publication that meets the requirements set forth in § 308.4(c) may include in such advertisement, in lieu of the cost disclosures required by § 308.3(b), a clear and conspicuous disclosure that a call to the advertised pay-per-call service may result in a substantial charge.
(b) The provider of any pay-per-call service that places an alphabetical listing in a publication that meets the requirements set forth in § 308.4(c) is not required to make any of the disclosures required by §§ 308.3 (b), (c), (d) and (f) in the alphabetical listing, provided that such listing does not contain any information except the name, address and telephone number of the pay-per-call provider.
(c) The publication referred to in § 308.4 (a) and (b) must be:
(1) Widely distributed;
(2) Printed annually or less frequently; and
(3) One that has an established policy of not publishing specific prices in advertisements.