Harvold, Egil P., 1912- <br/><br/>
The activator in interceptive orthodontics / 
Egil P. Harvold 
 - [Place of publication not identifed] :  [publisher not identified],  c1974 
<br/><br/> The activator in interceptive orthodontics, The 
<br/><br/><label>ISBN: </label>801620945 
<br/><br/><label>LC Class. No.: </label>RK 521 .H35 1974