
%0 Journal Article
%A Petersons, HF 
%T Disturbance Daily Variation During the IGY
%J Australian Journal of Physics
%D 1970/06/01
%V 23
%N 5
%P 905-926
%K 
%R https://doi.org/10.1071/PH700905
%U https://www.publish.csiro.au/paper/PH700905 
%X The disturbance daily variation field SD, was studied for the three seasons using lGY data from 50 observatories. Equivalent external and internal electric current systems which could account for the SD field were obtained by the method of spherical harmonic analysis. The external current systems were found to be only approximately symmetrical about the geomagnetic equator 
