Section 79 in The Appellate Side Rules of The High Court at Calcutta
79. Whenever production of any document from the custody of the Parliament, or a State Legislature, or a committee thereof and/or evidence of any officer in the Secretariat of the Parliament, or of the State Legislature or evidence of any officer of a committee thereof is required in a case pending before this court, a letter of request in the prescribed form [see Form No. 34 (Civil) Appendix - I] shall be issued instead of a summons in ordinary Form.
