Open Source Mathematical Software - documentation (Russian)

 SageMath is a free open-source mathematics software system licensed under the
 GPL. It builds on top of many existing open-source packages: NumPy, SciPy,
 matplotlib, Sympy, Maxima, GAP, FLINT, R and many more. Access their combined
 power through a common, Python-based language or directly via interfaces or
 wrappers.
 .
 Mission: Creating a viable free open source alternative to Magma, Maple,
 Mathematica and Matlab.
 .
 This package contains documentation in Russian.
 .
 Note that the package for English documentation (sagemath-doc-en) contains far
 more documentation than any of the other languages. So if you're finding this
 package lacking in content, then you could try that one as well.