On the classification of almost null rings

An almost null ring is a ring $R$ in which for all $a,b\in R$, $a^3=0$, $Ma^2=0$ for some square-free integer $M$ that depends on $a$ and $ab= ka^{2}=l b^{2}$ for some integers $k,l$. This paper is devoted to the classification of the almost null rings.