[Here][1] you can hear the pronounce by a Russian speaking person.


As to the romanization, which usually does have a standard form in any language, I'd use the one of the language you are writing in your paper. In English it is [Chebyshev][2] (not Chebychev). You can see the corresponding versions switching to other languages  from the linked article in en.wikipedia (list of languages on the left). 

[1]:http://www.forvo.com/word/%D0%BF%D0%B0%D1%84%D0%BD%D1%83%D1%82%D0%B8%D0%B9_%D0%BB%D1%8C%D0%B2%D0%BE%D0%B2%D0%B8%D1%87_%D1%87%D0%B5%D0%B1%D1%8B%D1%88%D0%B5%D0%B2/
[2]:http://en.wikipedia.org/wiki/Pafnuty_Chebyshev