(c)either (i) the exact interrogatories which it is desired to put to the witnesses, or the documents, etc., whose production is desired, or (ii) a clear and concise explanation of the exact points on which it is desired that the witnesses should be examined, or (iii) a request that notice should be given to the representatives of the parties to the action of the time when and of the place where evidence is to be taken, and that representatives of the parties should be allowed to put such questions to the witnesses as they may desire.