Gaidukov, P.G. РУССКИЕ ПОЛУДЕНГИ, ЧЕТВЕРЕТЦЫ И ПОЛУШКИ XIV–XVII ВВ. Moscow: Paleograf, 2006. 4to, original green cloth, gilt; jacket; cloth marker. 407, (1) pages; well-illustrated. English summary. Fine. The detailed standard work on Russian poludengi, chetveretsy and polushki of the 14th–17th centuries.