Dixon, Franklin W. <br/><br/>
The hypersonic secret /  
Franklin W. Dixon 
 - 151 pages ;  19 cm 
 - Hardy Boys mystery stories ; #135 .
 - Hardy Boys mystery stories ; #135. .
<br/><br/> "A Minstrel book." 
<br/><br/> Joe and Frank investigate the disappearance of their friend's father when the plane he was flying disappears over the Adirondack Mountains. 
<br/><br/> Primary 
<br/><br/><label>ISBN: </label>0671505181 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mystery and detective stories<br/>Detective and mystery fiction<br/>Detective and mystery stories<br/>Mystery fiction<br/>Hardy Boys (Fictitious characters)--Fiction
<br/><br/><label>Dewey Class. No.: </label>Fic.