Torres Quevedo, Leonardo (1901). «Machines á calculer». Impr. nationale (París). Mémoires Présentés par Divers Savants à l'Académie des Scienes de l'Institut de France (em francês). XXXII
Karl L. Wildes and Nilo A. Lindgren, A Century of Electrical Engineering and Computer Science at MIT, 1882-1982 (Cambridge, Massachusetts: MIT Press, 1985), pages 90-92.
Bedini, Silvio A.; Maddison, Francis R. (1966). «Mechanical Universe: The Astrarium of Giovanni de' Dondi». Transactions of the American Philosophical Society. 56 (5): 1–69. JSTOR1006002. doi:10.2307/1006002
Gomez-Jauregui, Valentin; Gutierrez-Garcia, Andres; González-Redondo, Francisco A.; Iglesias, Miguel; Manchado, Cristina; Otero, Cesar (1 de junho de 2022). «Torres Quevedo's mechanical calculator for second-degree equations with complex coefficients». IFToMM. Mechanism and Machine Theory. 172 (8): 104830. doi:10.1016/j.mechmachtheory.2022.104830
Rojas, R. (1998). «How to make Zuse's Z3 a universal computer». IEEE Annals of the History of Computing. 20 (3): 51–54. doi:10.1109/85.707574
Turing, A. M. (1937). «On Computable Numbers, with an Application to the Entscheidungsproblem». Proceedings of the London Mathematical Society. 2. 42 (1): 230–265. doi:10.1112/plms/s2-42.1.230
Bedini, Silvio A.; Maddison, Francis R. (1966). «Mechanical Universe: The Astrarium of Giovanni de' Dondi». Transactions of the American Philosophical Society. 56 (5): 1–69. JSTOR1006002. doi:10.2307/1006002