Rhodes, N.G. & Karl Gabrisch, C. Valdettaro, The Coinage of Nepal from the earliest times until 1911, London, 1989, 250 pages, 51 plates, hardcover with dust jacket, English text. The standard work; detailed and scholarly yet collector-friendly. Numismatic history, detailed catalog of all known varieties. Excellent plates illustrate multiple specimens. Includes Hill coinages & a chapter on Nepali coin use in Tibet.
Estimate: 100-150 USD