George Ritchey
1972 / The Ritchey-Chrétien Aplanatic Telescope: Letters from George Willis Ritchey to Elihu Thomson / Harold J. Abrahams / Proceedings of the American Philosophical Society 116 (1972) p. 486 [lien]
1976 / Ritchey, Curtis and the Discovery of Novae in Spiral Nebulae / M. A. Hoskin / Journal for the History of Astronomy 7 (1976) p. 47 [lien]