Section 91 Crpc - maintainable at appellate stage?

Hi all,

      Please let me know if petition under section 91 of Crpc for production of new documents is maintainable at appellate stage.?

      Preciously, in my case, the accused was convicted for a year by trial court and few valuable documents (like FIR of related case) were made known to me at appellate stage. Filed a petition u/s 91 r/w 391 crpc for production of such documents, where the maintainability of the same is being questioned now.

    Awaiting for useful responses.

Thank you all,