I.O.S. bulletin / 
 IOS bulletin  International Organization for Succulent Plant Study bulletin 
International Organization for Succulent Plant Study. 
 - volumes :  21-25 cm. 
 - Irregular. 
 -  no. 1 (Nov. 1961)- 
<br/><br/> Title from cover. 
<br/><br/><label>Subjects--Corporate Names: </label><br/>International Organization for Succulent Plant Study--Periodicals.