1. Bianchi, L.: Lezioni di geometria differenziale. Seconda edizione, riveduta e cosiderevolmente aumentata, in due volumi (1903) (Italian)
2. Blaschke, W.: Vorlesungen über Differentialgeometrie III, vol. 29. Springer Grundlehren XXIX, Berlin (1929)
3. Burstall, F., Hertrich-Jeromin, U.: The Ribaucour transformation in Lie sphere geometry. Differ. Geom. Appl. 24(5), 503–520 (2006)
4. Burstall, F., Hertrich-Jeromin, U., Lara Miro, M.: Ribaucour coordinates. Beitr. Algebra Geom. 60(1), 39–55 (2019)
5. Cho, J., Pember, M., Szewieczek, G.: Constrained elastic curves and surfaces with spherical curvature lines (preprint)