Books about Reproduction

The Renewal of Life; How and When to Tell the Story to the Young

Essays Upon Heredity and Kindred Biological Problems

The Works of Aristotle the Famous Philosopher

The Natural Philosophy of Love

The Biology, Physiology and Sociology of Reproduction

Physique de l'Amour: Essai sur l'instinct sexuel (French)

Über den Bildungstrieb (German)