Halperin & Sharir (2018), p. 724. Halperin, D.; Sharir, M. (2018), "Arrangements", in Goodman, Jacob E.; O'Rourke, Joseph; Tóth, Csaba D. (eds.), Handbook of Discrete and Computational Geometry, Discrete Mathematics and its Applications (3rd ed.), Boca Raton, Florida: CRC Press, pp. 723–762, ISBN978-1-4987-1139-5, MR3793131
Bern et al. (1991); an unpublished manuscript of Rom Pinchasi from 2011 claims the slightly stronger bound . Bern, M. W.; Eppstein, D.; Plassman, P. E.; Yao, F. F. (1991), "Horizon theorems for lines and polygons", in Goodman, J. E.; Pollack, R.; Steiger, W. (eds.), Discrete and Computational Geometry: Papers from the DIMACS Special Year, DIMACS Ser. Discrete Math. and Theoretical Computer Science (6 ed.), Amer. Math. Soc., pp. 45–66, MR1143288
Bern et al. (1991). Bern, M. W.; Eppstein, D.; Plassman, P. E.; Yao, F. F. (1991), "Horizon theorems for lines and polygons", in Goodman, J. E.; Pollack, R.; Steiger, W. (eds.), Discrete and Computational Geometry: Papers from the DIMACS Special Year, DIMACS Ser. Discrete Math. and Theoretical Computer Science (6 ed.), Amer. Math. Soc., pp. 45–66, MR1143288
Moreno & Prieto-Martínez (2021). Moreno, José Pedro; Prieto-Martínez, Luis Felipe (2021), "El problema de los triángulos de Kobon" [The Kobon triangles problem], La Gaceta de la Real Sociedad Matemática Española (in Spanish), 24 (1): 111–130, hdl:10486/705416, MR4225268
Martin (1996), pp. 41, 338. Martin, George E. (1996), The foundations of geometry and the non-Euclidean plane, Undergraduate Texts in Mathematics, Springer-Verlag, ISBN0-387-90694-0, MR1410263
Halperin & Sharir (2018), p. 724. Halperin, D.; Sharir, M. (2018), "Arrangements", in Goodman, Jacob E.; O'Rourke, Joseph; Tóth, Csaba D. (eds.), Handbook of Discrete and Computational Geometry, Discrete Mathematics and its Applications (3rd ed.), Boca Raton, Florida: CRC Press, pp. 723–762, ISBN978-1-4987-1139-5, MR3793131
Grünbaum (1972); Levi (1926); Roudneff (1988). Grünbaum, B. (1972), Arrangements and Spreads, Regional Conference Series in Mathematics, vol. 10, Providence, R.I.: American Mathematical Society Levi, F. (1926), "Die Teilung der projektiven Ebene durch Gerade oder Pseudogerade", Ber. Math.-Phys. Kl. Sächs. Akad. Wiss. Leipzig, 78: 256–267 Roudneff, J.-P. (1988), "Arrangements of lines with a minimum number of triangles are simple", Discrete & Computational Geometry, 3 (1): 97–102, doi:10.1007/BF02187900
Moreno & Prieto-Martínez (2021). Moreno, José Pedro; Prieto-Martínez, Luis Felipe (2021), "El problema de los triángulos de Kobon" [The Kobon triangles problem], La Gaceta de la Real Sociedad Matemática Española (in Spanish), 24 (1): 111–130, hdl:10486/705416, MR4225268