Fisher, Irving. _National Vitality._ Washington, 1910. U.S. 61st Cong., 2d Sess. Senate Doc. 419. Hall, W.S. _Biology, Physiology, and Sociology of Reproduction_ also, _Sexual Hygiene._ Ed. 11. Chicago, 1906. Keyes, E.L. _Observations of the Persistence of Gonococci in the Male Urethra._ American Journal of the Medical Science, January, 1912. Morrow, P.A. _Social Diseases and Marriage._ Philadelphia, 1904. Taylor, R.W. _Practical Treatise on Genito-Urinary and Venereal Diseases and Syphilis._ Ed. 3. Philadelphia, 1904. CHAPTER V ECONOMIC PHASES Adams, T.S., _and_ Sumner, H.L. _Labor Problems._ Ed. 8. New York, 1911. Chap. I. Addams, Jane. _A New Conscience and an Ancient Evil._ New York, 1912. Butler, E.B. _Women and the Trades._ New York, 1909. Flexner, Abraham. _Prostitution in the United States._ New York. (In preparation.) Bureau of Social Hygiene Publications. ---- _Prostitution in Western Europe._ New York, 1913. Bureau of Social Hygiene Publications. Fosdick, R.D. _European Police Systems._ New York, 1913. Bureau of Social Hygiene Publications. Goldmark, Josephine. _Fatigue and Efficiency._ New York, 1912. Kelley, Florence. _Some Ethical Gains through Legislation._ New York, 1905. Kneeland, G.J. _Commercialized Prostitution in New York City._ New York, 1913. Bureau of Social Hygiene Publications. More, L.B. _Life Earner's Budgets; A Study of Standards and Cost of Living in New York City._ New York, 1907. Roe, C.G. _Panders and their White Slaves._ Chicago, 1910. Ryan, J.A. _A Living Wage._ New York, 1910. Sanger, W.W. _History of Prostitution._ New York, 1913. Seligman, E.R.A., ed. _Social Evil._ Ed. 2, rev. New York, 1912. Chap. I. Streightoff, F.H. _Standard of Living among Industrial People of America._ Boston, 1911. U.S. Bureau of Labor. _Women and Child Wage-Earners in the United States._ Washington, 1911-12. Vols. 5, 15. U.S. Immigration Commission. _Steerage Conditions; Importation and Harboring Women for Immoral Purposes...._ Washington, 1911. U.S. 61st Cong., 3d Sess. Senate Doc. 753. Reports of Commission, vol. 37. Vice Commission Reports. A list of vice commissions is printed at the end of these references. CHAPTER VI RECREATIONAL PHASES Addams, Jane. _Spirit of Youth and the City Streets._ New York, 1912. Allen, W.H. _Civics and Health._ Boston, 1909. Camp-Fire Girls of America. _Manual._ New York, 1913. Chicago Vice Commission. _Report_, 1911. Collier, John. _Moving Pictures; Their Function and Proper Regulation._ Playground Magazine, vol. 4, pp. 232-39, October, 1910. _Health Department Control of Venereal Diseases. Social Diseases_, vol. 2, nos. 2-3, April and July, 1911. Israels, Mrs. C.H. _Dance Problem._ Playground Magazine, vol. 4, pp. 242-50, October, 1910. Juvenile Protective Association of Chicago. Reports on dance halls, moving picture theaters, saloons, department stores, etc. Chicago, 1911-12. Minneapolis Vice Commission. _Report_, 1911, pp. 129-31.