1. An excellent general reference is M. A. B. Brazier, A History of the Electrical Activiry of the Brain: The First Half-century, London: Pitman, 1961.
2. Richard Caton, “The electric currents of the brain,” Brit. Med. J. 2: 278, 1875.
3. Richard Caton, “Interim report on investigation of the electric currents of the brain,” Brit. Med. J. Suppl. 1: 62–65, 1877.
4. Adolf Beck, “The determination of localization in the brain and spinal cord by means of electrical phenomena” (in Polish), Polska Akademiia Umiejetnthci (Ser. 2): 187–232, 1892.
5. Adolf Beck, “Die Bestimmung der Localisation der Gehirn- und Riickenmarkfunctionen vermittelst der electrischen Erscheinungen,” Centra/blatt der Physio%gie4: 473–476, 1890.