Whenever a party is required to satisfy the Commission or the Registrar that a copy of a referral, objection or other document has been served on another party, the party so required must provide the Commission or Registrar with-
a copy of the proof of mailing the referral, objection or other document by registered post to the other party;
a copy of the telegram, telex or telefax communicating the referral, objection or other document to the other party;
a copy of a receipt signed by the other party or on that party's behalf if the copy of the referral, objection or other document was delivered by hand; or
a statement confirming service signed by the person who delivered a copy of the referral, objection or other document to the other party.