 His transplantation work was widely reported inside the Soviet Union, where it was continuously criticized for being unethical, but it was not until the late 1950s that news of his experiments spread to the outside world.In fact, by the time American surgeons became aware of Demikhov's dog head transplantations in 1959, he had already been performing these procedures for five years.Demikhov coined the word "transplantology", meaning organ transplantation, in his 1960 monograph "Experimental Transplantation of Vital Organs", for which he received his doctoral degree.