Enid Blyton <br/><br/>
Secret Seven Win Through 

<br/><br/> The Seven have a fantastic new hiding place. But someone else is using it at night - and it's Jack's little sister Susie who helps them catch the intruder. 
<br/><br/><label>ISBN: </label>9780340917602 
<br/><br/><label>Dewey Class. No.: </label>English BLY