1. Di Benedetto, F.: Su alcune proprietà notevoli del rotore del vento di gradiente. Annali Geofis. (1953).
2. Brunt, D.: Physical and Dynamical Meteorology. Cambridge Univ. Press. 1944, p. 197–198.
3. Pettersen, S.: Contribution to the theory of pressure variations. Aerology Section, NAVAER 50-IR-174, Washington, D. C., 1945.
4. Sutcliffe, R. C.: Historical weather maps, Northern Hemisphere: Charts of maximum and minimum Thickness lines 1000/500 mb, Northern Hemisphsphere, 1946–1950. Air Weather Service.