aplan├ętisme

[1972] The Ritchey-Chr├ętien Aplanatic Telescope: Letters from George Willis Ritchey to Elihu Thomson ; Harold J. Abrahams ; Proceedings of the American Philosophical Society 116 (1972) p. 486 [lien]
[1982] The First Aplanatic Object Glass ; J. A. Bennett ; Journal for the History of Astronomy 13 (1982) p. 206 [lien]