Naked man posing sexually. Standing Male Nude from Behind (1893) by Otto Greiner. Original from The National Gallery of Art.… https://www.rawpixel.com/image/2467782/free-illustration-image-male-nudes-anatomy-man-bodyFree Image from public domain licenseOdysseus and the Sirens. Colour process print after O. Greiner, 190-. https://www.rawpixel.com/image/13952644/odysseus-and-the-sirens-colour-process-print-after-greiner-190Free Image from public domain license