17 CFR §260.0-4

The manually signed original (or in the case of duplicate originals, one duplicate original) of all registrations, applications, statements, reports, or other documents filed under the Trust Indenture Act of 1939 shall be numbered sequentially (in addition to any internal numbering which otherwise may be present) by handwritten, typed, printed, or other legible form of notation from the facing page of the document through the last page of that document and any exhibits or attachments thereto. Further, the total number of pages contained in a numbered original shall be set forth on the first page of the document.