Két pótolhatatlan forrás a Magyar-Róng ügyben:
Mainwaring, George B. A Grammar of the Róng (lepcha) Language: As It Exists in the Dorjeling Und Sikim Hills. Calcutta: Printed by C.B. Lewis, 1876. Print.
Mainwaring, George B, and Albert Grünwedel. Dictionary of the Lepcha-Language. Berlin: Printed by Unger Bros, 1898. Print.