System of generators of differential skew field of $Sp(n)$-invariant differential rational functions with quaternion variables

Let ${{H}^{n}}$ be an n dimensional (the left) vector space over the skew-field of quaternion numbers, and $Sp\left( n \right)$ be a group of symplectic transformations of ${{H}^{n}}$. Also, the skew-field of all $Sp\left( n \right)$-invariant non-commutative differential rational functions denoted by $\Re {{\left[\!\left[ x,\bar{x} \right]\!\right]}^{Sp\left( n \right)}}$. In this talk an explicit description of a finite generating system in the differential skew-field $\Re {{\left[\!\left[ x,\bar{x} \right]\!\right]}^{Sp\left( n \right)}}$ is considered.