[716] A. Hegar, “The Sexual Impulse,” pp. 58, 59, 104, 105 (Stuttgart, 1894).
[717] M. Gruber, “Hygiene of the Sexual Life,” pp. 60-62 (Stuttgart, 1905).
[718] L. Löwenfeld, “The Sexual Life and Nervous Disorders,” pp. 154-156.
[719] C. Hasse (Mensinga), “Facultative Sterility,” fourth edition (Berlin and Neuwied, 1885); same author, “How is the Life of Married Women best Safeguarded?” (Berlin and Neuwied, 1895); same author, “Prognosis of Married Life for Women” (Berlin and Neuwied, 1892); same author, “Vom Sichinachtnehmen” [Coitus interruptus, see [p. 702]] (Neuwied, 1905).
[720] P. Fürbringer, “Sexual Hygiene in Married Life,” published in Senator and Kaminer’s, “Health and Disease in Relation to Marriage and the Married State,” p. 209 (London, Rebman Limited, 1906).
[721] Spener, the article “Artificial Sterility,” published in Eulenburg’s Encyclopedic Annual of the Medical Sciences, vol. i., pp. 456-459 (Berlin and Vienna, 1903).
[722] L. Bergeret, “Des Fraudes dans l’Accomplissment des Fonctions Génératrices,” fourteenth edition (Paris, 1893). See also Toulouse, “Les Conflits Intersexuels,” pp. 41-58 (Paris, 1904).
[723] H. Ferdy, “Means for the Prevention of Conception,” eighth edition, two parts (Leipzig, 1907); same author, “Moral Self-restraint: the Reflections of a Malthusian” (Hildesheim, 1904).
[724] Karl Buttenstedt, “Happiness in Marriage (Revelation in Woman): a Nature Study,” third edition (Friedrichshagen, 1904).
[725] Richard E. Funcke, “A New Revelation of Nature: a Secret of the Sexual Life. No more Prostitution” (Hanover, 1906).