1. Livens , G.H. 1918.The Theory of Electricity, 398–400. Cambridge University Press. §§ 451–453
2. Gray , Mathews and MacRobert . 1922.Treatise on Bessel Functions, 58–58. Macmillan & Co. § 3Watson, ‘Theory of Bessel Functions,’ § 7.23, p. 202 (Cambridge University Press, 1922).
3. Gray and Mathews .Bessel Functions58–58.