Section 50C(2) in The Indian Post Office Rules, 1933
(2)[ The International Speed Post Documents and International Speed Post Merchandise may be booked at the places and post offices as specified by head of circles from time to time.] [Substituted by Notification No. G.S.R. 1475(E), dated 1.12.2017 (w.e.f. 30.3.1933).]