Magnetic vertical intensity epcoh 1955, 1702 world 

 - USA  U. S. Hydrographic Office 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Magnetic Vertical Intensity EpcohVertical Intensity Epcoh
<br/><br/><label>Universal Decimal Class. No.: </label>538(084.2)  / USH