(3) In the case of appointment of an agent, service upon the agent of any document relating to the proceeding or matter shall be taken to be service upon the person appointing the agent and all communications directed to be made to that person in respect of the proceeding or matter may be addressed to his or her agent, and all attendances upon the registrar relating to the proceeding or matter may be made by or through the agent. (4) In any particular case the registrar may require the personal signature or presence of an applicant, opponent, proprietor, registered user or other person. 11. Register of agents. The registrar shall keep a register of trademark agents in Uganda. 12. Classification of goods and services. (1) For the purposes of trade mark registration and the registration of trademark users made under the Act, goods and services are classified in accordance with the Third Schedule to these Regulations. (2) For the purposes of classifying goods and services in accordance with the Third Schedule and of interpreting that Schedule, reference shall be had to the 9th Edition of the International Classification of Goods and Services for the purposes of the registration of marks under the Nice Agreement of 15 June 1957 (as revised) published by the World Intellectual Property Organisation in 1992, including the explanatory notes and lists of goods and services published therein. (3) Where the 9th Edition of the International Classification of Goods and Services, is amended by the World Intellectual Property Organisation at any future stage, the Minister, on the advice of the Registrar, shall publish the amendments in the Gazette and shall, to the extent that the amendments necessitate an amendment of the Third Schedule, amend the Third Schedule and publish the amendment in the Gazette. (4) If any doubt arises as to the class in which any particular description of goods or services belongs, the matter shall be determined by the registrar. 1997