Camacho, Mariano Jesús (15 February 2016). "En busca de la esfera de Dios" [In search of the sphere of God]. Vavel (in Spanish). Retrieved 10 March 2016.
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Camacho, Mariano Jesús (15 February 2016). "En busca de la esfera de Dios" [In search of the sphere of God]. Vavel (in Spanish). Retrieved 10 March 2016.