Freiberg Hoffmann, A., G. de la Iglesia, J. Beatriz Stover, and M. Fernández Liporace. “Paradoxical Personality Scale: Its Development and Construct Validity Analysis”. International Journal of Psychological Research, vol. 7, no. 1, Jan. 2014, pp. 49-72, doi:10.21500/20112084.667.