Shawyer & Watson 1994, hlm. 32. Shawyer, Bruce; Watson, Bruce (1994). Borel's Methods of Summability: Theory and Application. Oxford Mathematical Monographs. The Clarendon Press, Oxford University Press, New York. ISBN0-19-853585-6. MR1320266.
Ferraro 1999, hlm. 130. Ferraro, Giovanni (Juni 1999). "The First Modern Definition of the Sum of a Divergent Series: An Aspect of the Rise of 20th Century Mathematics". Archive for History of Exact Sciences. 54 (2): 101–135. doi:10.1007/s004070050036.Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Ferraro 1999, hlm. 118; Tucciarone 1973, hlm. 10. Ferraro mengkritik penjelasan Tucciarone (p. 7) tentang bagaimana Hölder sendiri memikirkan hasil umum, tetapi penjelasan kedua penulis mengenai perlakuan Hölder terhadap 1 − 2 + 3 − 4 + ... serupa. Ferraro, Giovanni (Juni 1999). "The First Modern Definition of the Sum of a Divergent Series: An Aspect of the Rise of 20th Century Mathematics". Archive for History of Exact Sciences. 54 (2): 101–135. doi:10.1007/s004070050036.Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan) Tucciarone, John (Januari 1973). "The development of the theory of summable divergent series from 1880 to 1925". Archive for History of Exact Sciences. 10 (1–2): 1–40. doi:10.1007/BF00343405.Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Ferraro 1999, hlm. 123–128. Ferraro, Giovanni (Juni 1999). "The First Modern Definition of the Sum of a Divergent Series: An Aspect of the Rise of 20th Century Mathematics". Archive for History of Exact Sciences. 54 (2): 101–135. doi:10.1007/s004070050036.Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Ferraro 1999, hlm. 120–128. Ferraro, Giovanni (Juni 1999). "The First Modern Definition of the Sum of a Divergent Series: An Aspect of the Rise of 20th Century Mathematics". Archive for History of Exact Sciences. 54 (2): 101–135. doi:10.1007/s004070050036.Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)