1. S.-B. Zur Morphologie geophysikalischer Zeitfunktionen;Bartels;Preussische Akademie der Wissenschaften,1935
2. Random fluctuations persistence, and quasi persistence in geophysical and cosmical periodicities;Bartels;Terrestrial Magnetism and Atmospheric Electricity,1935
3. Changes in the geomagnetic field and solar wind — causes of changes of climate and atmospheric circulation
4. Calder, N., 1997. Manic Sun: Weather Theories Confounded. Pilkington Press Ltd., Yelvertoft Manor, Yelvertoft, Northamptonshire, UK.
5. Annual variation of geomagnetic activity;Clúa de Gonzales;Journal of Atmospheric and Solar-Terrestrial Physics,2001