Special modules over Jordan algebras

In this paper we study special representations of finite-dimensional Jordan algebra $J$ whose $Rad^2 J=0$. For each Jordan algebra $J$ of this class we consider its Tits-Kantor-Koecher construction $TKK(J)$ and then associate to the latter a quiver with relations $Q$ such that the category of representations of $Q$ is isomorphic to the category of special representations of $J$.