Atlas of the Ovulation Method:  The Mucus Patterns of Fertility and Infertility/ 
by Evelyn L. Billings, John J. Billings, Maurice Catarinich; with appendex on The Scientific Basis of the Ovulation Method by James B. Brown, 
 - 4th ed.- 
 - melbourne:  Advocate Press,  1980 
 - v, 87 p.:  ill.[some col.]  22 cm. 
<br/><br/><label>ISBN: </label>858260883 
<br/><br/><label>LC Class. No.: </label>RG136.5  / .B5 1980