Stephen S Yau 
Gorenstein Quotient Singularities in Dimension Three [PDF ebook] 

If $G$ is a finite subgroup of $GL(3, {/mathbb C})$, then $G$ acts on ${/mathbb C}^3$, and it is known that ${/mathbb C}^3/G$ is Gorenstein if and only if $G$ is a subgroup of $SL(3, {/mathbb C})$. In this work, the authors begin with a classification of fi