Blyton, Enid <br/><br/>
Well done, secret seven 

 - London  Hodder Children's  2002 
 - 118 
 - Secret Seven .
<br/><br/> The Secret Seven have built a new meeting place, and it's a tree house. But someone else has discovered their hideout, and he's on the run from a gang of thieves 
<br/><br/><label>ISBN: </label>9780340796382 
<br/><br/><label>Dewey Class. No.: </label>823  / BLY-W