Cleminson, Richard. «“A Century of Civilization under the Influence of Eugenics” : Dr. Enrique Diego Madrazo, Socialism and Scientific Progress». Dynamis: Acta Hispanica Ad Medicinae Scientiarumque Historiam Illustrandam, vol. 26, agost 2008, p. 221-5, https://raco.cat/index.php/Dynamis/article/view/114238.