https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/14015063
Four male écorchés or partially flayed figures; the first and the third have proportional markings. Etching by J. García Hidalgo, ca. 1691.
Original public domain image from Wellcome Collection
Public DomainFree CC0 image for Personal and Business use