Ingrid D. Rowland, Giordano Bruno. Philosopher / Heretic, 2009, p. 224
harvard.edu
adsabs.harvard.edu
J.B. Hartung (1976): 'Was the formation of a 20-km-diameter impact crater on the moon observed on June 18, 1178', in: Meteoritics, vol. 11, 30 sept. 1976, pp. 187-194 (online tekst).