Physical climatology / by Helmut Landsberg Landsberg, Helmut Erich, 1906-1985. Climatology. QC981 .L3 1941 551.59 LAP Includes index. "General references": p. 272. "Special references": p. 273-277. State College, Pa. : School of mineral industries, The Pennsylvania State college, 1941. 1941. 1941 Text xii, 283 p. : eng