Cita APA (7th ed.)
Udías Vallina, A. Searching the Heavens and the Earth: The History of Jesuit Observatories. Kluwer.
Cita Chicago (17th ed.)
Udías Vallina, Agustín. Searching the Heavens and the Earth: The History of Jesuit Observatories. Dordrecht, Holanda: Kluwer.
Cita MLA (9th ed.)
Udías Vallina, Agustín. Searching the Heavens and the Earth: The History of Jesuit Observatories. Kluwer.
Atenció: Aquestes cites poden no estar 100% correctes.