50 No. 3 Electronic and Postal Communications 2010 licensee by written notice to cease or refrain from taking such action, as the case may be. (5) A person who contravenes any of the provisions of this section commits an offence and shall be liable on conviction to a fine not exceeding twenty thousand US dollars or its equivalent in Tanzania shillings. Powers of the Authority on dominant licensee 61. The Authority shall have powers to determine dominant position of electronic communication licensee in the relevant market. (b) Competition practices Electronic communications licensees holding a dominant position 62.(1) The Authority shall, not later than 31 December of each year, publish in the Gazette a list for the following calendar year of (a) all electronic communications markets that will or are likely to exist; and (b) electronic communications licensees determined by the Authority to hold for each electronic communications market a dominant position. (2) The Authority shall determine an electronic communications licensee to hold a dominant position in a given electronic communications market for a given calendar year for the electronic communications market and the electronic communications licensee has more than thirty five percent, acting alone, be able to profitably and materially restrain or reduce competition. (3) The Authority shall produce and make public guidelines, for use by the Authority, on the manner of defining an electronic communications market and of determining whether a licensee holds a dominant position therein.