Annals of the International Geophysical Year  v. XVIII : tables of IGY monthly median ionospheric data 
edited by W. J. G. Beynon and C. M. Minnis 
 - Oxford  Pergamon Press  1962 
 - 461p. 
 - Annals of the International Geophysical Year; v. 18 .
<br/><br/><label>ISBN: </label>1483226379 
<br/><br/><label>Subjects--Topical Terms: </label><br/>International Geophysical Year
<br/><br/><label>Universal Decimal Class. No.: </label>550.38  / BEY