Bartels, J <br/><br/>
Geomagnetic indices k and c, 1954 
J. Bartels and J Veldkemp                                                   
 - Washington  1955 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geomagnetic indices
<br/><br/><label>Universal Decimal Class. No.: </label>083.550.38  / IAGA-12I