17
Social Problems; Their Treatment, Past, Present and Future, p. 8, London, 1912.
18
Stetson, G. R., "Memory Tests on Black and White Children," Psych. Rev., 1897, p. 285. Véase también MacDonald, A., en Rep. U. S. Comm. of Educ., 1897-98.
19
Mayo, M. J., "The Mental Capacity of the American Negro," Arch. of Psych., No. 28.
20
Phillips, B. A., "Retardation in the Elementary Schools of Philadelphia," Psych. Clinic, VI, págs. 79-90; "The Binet Tests Applied to Colored Children," ibíd., VIII, págs. 190-196.