"by Carolyn Keene" <br/><br/>
The clue of the black keys 

 -  New York : Grosset & Dunlap, c1968.  1968 
 - 174 
<br/><br/><label>ISBN: </label>0448095289 
<br/><br/><label>Dewey Class. No.: </label>F823  / 1828