Psychopathia Sexualis by Richard von Krafft-Ebing
"Psychopathia Sexualis" is a seminal work in the field of sexual psychopathology that compiles numerous case studies of atypical sexual behaviors. Written in the late 19th century, the book categorizes and examines a wide range of sexual deviations and disorders, exploring their psychological and medical aspects. The author, a noted psychiatrist, uses clinical observations to argue that sexual deviance is often linked to mental disorders. This work significantly influenced both the medical and legal understanding of human sexuality at the time, contributing to the emerging fields of psychiatry and forensic pathology.