Practitioners shall file a declaration that they are authorized to represent the particular party on whose behalf they appear at the time of making an initial appearance, in all proceedings. This requirement can be met by:

(a) Entering the practitioner's name as the representative of an applicant in the appropriate space on an application form;

(b) Signing any complaint, petition, protest, reply or other pleading with a designation following the practitioner's signature that he is the representative of a party;

(c) Entering an appearance at any hearing on the form provided; or

(d) Filing a letter with the Chief, Section of Administration, Office of Proceedings, Surface Transportation Board stating that practitioner is authorized to represent a party. The party represented, their address, and the docket number of the proceeding must also be identified at the time of the initial appearance.