Bartels, J. <br/><br/>
Geomagnetic data Indices K and C, 1962 
J. Bartels, A. Romaņa and J. Veldkamp. 
 - Holland  IUGG Publications  1965 
 - 101p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geomagnetic data<br/>Geomagnetic data Indices
<br/><br/><label>Universal Decimal Class. No.: </label>083.550.38  / IAGA-12Q1