|Continental Holiday. The American Travel Guide to Europe. New York, 1961.|
Ernst Leitz GmbH of Wetzlar, Germany made around 82,000 of these cameras between 1957 and 1968. The "M" within the nomenclature of this series of cameras comes from the first initial of "Meßsucher" (or "Messsucher"), which is the German word for "Rangefinder". Examples sell for over $1000 these days. Somebody on ebay is even asking $18,999 for just a body!