Keene, Carolyn. <br/><br/>
The clue in the crossword cipher. 

 - New York :  Grosset,  1967. 
 - 177 p. :  ill. 
 - Her Nancy Drew mystery stories .
<br/><br/> A Nancy Drew mystery. 
<br/><br/><label>LCCN: </label>67005330 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mystery fiction.
<br/><br/><label>Dewey Class. No.: </label>Fic