Robuta

https://www.scirp.org/reference/ReferencesPapers?ReferenceID=1745591
Byrd, P.F. and Friedman, M.D. (1971) Handbook of Elliptic Integrals for Engineers and Scientists. 2nd Edition, Springer-Verlag, Berlin.
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https://www.boost.org/doc/libs/1_80_0/libs/math/doc/html/math_toolkit/ellint/ellint_1.html
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