SUMMERS, J.K. <br/><br/>
PRACTICAL AIR NAVIGATION SIMPLY EXPLAINED 
J.K. SUMMERS 
 - LONDON  SIR ISAAC PITMAN & SONS,LTD  1941 
 - 57 
<br/><br/> Rs mean Reading Circle Page 1250-1275 in A-Z Register (Acc. No. Rs1-Rs717)  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Reading Circle
<br/><br/><label>Dewey Class. No.: </label>RS475