Ionospheric radio propagation 

 - Washington :   National bureau of standars,   1948. 
 - 209 p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>ONDAS ACUSTICAS<br/>PROPAGACION DE ONDAS<br/>IONOSFERA
<br/><br/><label>Universal Decimal Class. No.: </label>621.371