Provisional GSGS series 4229. First Edition. Copied from an Italian Istituto Geografico Militare map dated 1934 with principal communications revised using smaller scale material from 1938. Compiled by the U.S. Army Map Service in 1944. The meridians are based on the meridian of Rome, which is 12 degrees, 27 minutes and 7.1 seconds east of Greenwich. Contour Interval 50 metres. North Italy Zone Grid.