Gutmann has also provided testimony on his findings before U.S. Congress and European Parliament, and in August 2014 published his investigation as a book titled “The Slaughter: Mass Killings, Organ Harvesting and China’s Secret Solution to Its Dissident Problem.”
Gutmann on myös todistanut aiheesta Yhdysvaltain kongressissa ja Euroopan parlamentissa, ja elokuussa 2014 hän julkaisi tutkimuksensa kirjana nimeltä The Slaughter: Mass Killings, Organ Harvesting and China’s Secret Solution to Its Dissident Problem.