See for example, Folland, Gerald B. (2009). "Convergence and completeness". Fourier Analysis and its Applications (Reprint of Wadsworth & Brooks/Cole 1992 ed.). American Mathematical Society. pp. 77ff. ISBN978-0-8218-4790-9. Archived from the original on 2015-03-19.
See Plofker, Mathematics in India, Princeton University Press, 2009, p. 257 See "Clark University". Archived from the original on 2008-06-15. See Maor (1998), chapter 3, regarding the etymology.
Heß, Adolf (1926) [1916]. Trigonometrie für Maschinenbauer und Elektrotechniker - Ein Lehr- und Aufgabenbuch für den Unterricht und zum Selbststudium (in German) (6 ed.). Winterthur, Switzerland: Springer. doi:10.1007/978-3-662-36585-4. ISBN978-3-662-35755-2.
Spivak, Michael (1967). "15". Calculus. Addison-Wesley. pp. 256–257. LCCN67-20770.
Nielsen (1966, pp. xxiii–xxiv) Nielsen, Kaj L. (1966), Logarithmic and Trigonometric Tables to Five Places (2nd ed.), New York: Barnes & Noble, LCCN61-9103
O'Connor, J. J.; Robertson, E. F. "Madhava of Sangamagrama". School of Mathematics and Statistics University of St Andrews, Scotland. Archived from the original on 2006-05-14. Retrieved 2007-09-08.
See for example, Folland, Gerald B. (2009). "Convergence and completeness". Fourier Analysis and its Applications (Reprint of Wadsworth & Brooks/Cole 1992 ed.). American Mathematical Society. pp. 77ff. ISBN978-0-8218-4790-9. Archived from the original on 2015-03-19.
O'Connor, J. J.; Robertson, E. F. "Madhava of Sangamagrama". School of Mathematics and Statistics University of St Andrews, Scotland. Archived from the original on 2006-05-14. Retrieved 2007-09-08.
See Plofker, Mathematics in India, Princeton University Press, 2009, p. 257 See "Clark University". Archived from the original on 2008-06-15. See Maor (1998), chapter 3, regarding the etymology.