Author Anil Bohora writes:

Banknotes of Bhutan
By Anil R. Bohora & Gylfi K. Snorrason

First Edition: 2009
ISBN 978-81-7525-881-5

Monetary reform commenced in 1974, during the reign of the King, Druk Gyalpo Jigme Singye Wang-chuck, with the issue by the Ministry of Finance of the first bank notes on April 6, 1974 coinciding with His Majesty's Coronation on 2 June 1974.

The unit of currency was standardized with 100 Chhetrum being equal to 1 Ngultrum.

The ISO 4217 Code for Bhutanese Ngultrum is "BTN".

In 1982 Royal Monetary Authority of Bhutan (RMA) was established to act as the central bank of Bhutan.The RMA commenced its operations in 1983, when it assumed liability for all notes and coins previouslyissued by the Ministry of Finance.

Banknotes were issued by the Royal Government of Bhutan until October 31, 1983 and by Royal MonetaryAuthority of Bhutan beginning on November 1, 1983 as a result of Royal Monetary Authority of BhutanAct of August 1982.

To read the complete book, see:
Banknotes of Bhutan(https://foxly.link/BanknotesOfBhutan)