Ward's Natural Sci. Bulletin 

 - New York  Natural Sci. Buttetin  1951 
 - 15 
 - No. 1 .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Am73:M81
<br/><br/><label>Dewey Class. No.: </label>Am73:M81  / A.25