About Nikolay Yakovlevich Sonin
Nikolay Yakovlevich Sonin, Russian mathematician and academic (died 1915) Nikolay Yakovlevich Sonin (Russian: Никола́й Я́ковлевич Со́нин, February 22, 1849 – February 27, 1915) was a Russian mathematician. Sonin worked on special functions, in particular cylindrical functions. For instance, the Sonine formula is a formula given by Sonin for the integral of the product of three Bessel functions. Together with Andrey Markov, Sonin prepared a two volume edition of Chebyshev's works in French and Russian.
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