Alvar, Jaime, “Matériaux Pour L'étude De La Formule Sive Deus, Sive Dea.” Numen, vol. 32, no. 2, 1985, pp. 236–273, JSTOR, [1]
Mary Beard, "Cicero's 'Response of the haruspices' and the Voice of the Gods", pp. 28-29 in The Journal of Roman Studies, Vol. 102 (2012), pp. 20-39, Society for the Promotion of Roman Studies, available at JSTOR[2] (subscription required)