WELTER Gerhard, "CLEANING AND PRESERVATION OF COINS AND MEDALS / Including Paper Money, Restoration and Preservation by James J. Curto", Sanford J. Durst, New York, N.Y., 1980. 2nd edition (1st in 1976), in 8vo, p. ix+118. An early guide on cleaning and preservation of many types of coins and medal. Full leather bound, gilt title on spine and front cover. Near fine.