Related documents
The rhythm of sterility and fertility in women
A discussion of the physilogical, practical and ethical aspects of the discoveries of Dr. K. Ogino, Japan, and Prof. H. Knaus, Germany, regarding the periods when conception is impossible and when possible.
Geburtenregelung
Empfängnisverhütung: Problem und Praxis
Pessary
United States Patent Office: No. 29,408
Der Ehekalender "Konzip"
