Billings, John J. <br/><br/>
The Ovulation Method :  The avoidance of pregnancy in medical practice, by a technique which is safe, reliable and morally acceptable / 
John J. Billings. 
 - Melbourne :  The Advocate Press,   1967. 
 - 95 p. 
<br/><br/><label>Dewey Class. No.: </label>241.64  / BIL