@book{ Solr-4469872, title = {Normal weather maps, Northern Hemisphere sea level pressure.}, editor = {United States. Weather Bureau}, editor = {United States. Army Air Forces}, address = {Washington,}, year = {1946}, note = {Cover title.}, note = {Prepared by the Weather Bureau and the Army Air Forces.}, note = {"Based on the 40 1/2-year period, 1899 to 1939, covered by the Daily synoptic series, Northern Hemisphere weather maps, sea level."}, }