"It has been written by a man, in an attempt to explain our sort that the ordinary world will understand us"
German version of 'Psychoapthia Sexualis'
Creative Commons AttributionGerman version of 'Psychoapthia Sexualis' - Credit: Krafft-Ebing (H.-P. Haack, Wikimedia Commons)

Most probably Psychopathia Sexualis (1886) by Richard Freiherr von Krafft-Ebing.

The book consisted of a series of case studies of human sexuality; it included discussions of sadism and masochism, two terms which were coined by Krafft-Ebing. 

With a Latin title and partly written in Latin, the book was intended for a professional audience, but it became a bestseller amongst the general public. It was translated into English in 1892.

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