Beresnevich, Victor; Ramírez, Felipe; Velani, Sanju (2016), "Metric Diophantine approximation: Aspects of recent work", in Badziahin, Dzmitry; Gorodnik, Alexander; Peyerimhoff, Norbert (eds.), Dynamics and Analytic Number Theory: Proceedings of the Durham Easter School 2014, London Mathematical Society Lecture Note Series, vol. 437, Cambridge University Press, pp. 1–95, arXiv:1601.01948, doi:10.1017/9781316402696.002, ISBN978-1-316-40269-6, S2CID119304793. See Theorem 1.33 (the Jarník–Besicovitch theorem), p. 23, and the discussion following the theorem.
Durnová, Helena (2004), "A history of discrete optimization", in Fuchs, Eduard (ed.), Mathematics Throughout the Ages, Vol. II, Prague: Výzkumné centrum pro dějiny vědy, pp. 51–184, ISBN9788072850464. See in particular page 127: "Soon after Borůvka's published his solution, another Czech mathematician, Vojtěch Jarník, reacted by publishing his own solution," and page 133: "Jarník’s article on this topic is an extract from a letter to O. Borůvka".
Beresnevich, Victor; Ramírez, Felipe; Velani, Sanju (2016), "Metric Diophantine approximation: Aspects of recent work", in Badziahin, Dzmitry; Gorodnik, Alexander; Peyerimhoff, Norbert (eds.), Dynamics and Analytic Number Theory: Proceedings of the Durham Easter School 2014, London Mathematical Society Lecture Note Series, vol. 437, Cambridge University Press, pp. 1–95, arXiv:1601.01948, doi:10.1017/9781316402696.002, ISBN978-1-316-40269-6, S2CID119304793. See Theorem 1.33 (the Jarník–Besicovitch theorem), p. 23, and the discussion following the theorem.
Beresnevich, Victor; Ramírez, Felipe; Velani, Sanju (2016), "Metric Diophantine approximation: Aspects of recent work", in Badziahin, Dzmitry; Gorodnik, Alexander; Peyerimhoff, Norbert (eds.), Dynamics and Analytic Number Theory: Proceedings of the Durham Easter School 2014, London Mathematical Society Lecture Note Series, vol. 437, Cambridge University Press, pp. 1–95, arXiv:1601.01948, doi:10.1017/9781316402696.002, ISBN978-1-316-40269-6, S2CID119304793. See Theorem 1.33 (the Jarník–Besicovitch theorem), p. 23, and the discussion following the theorem.