are there fixed context sensitive grammars which are PSPACE complete? wikipedia entry  says without reference that 

"There are even some context-sensitive grammars whose fixed grammar recognition problem is PSPACE-complete."

This is stronger than saying that CSG is PSPACE-complete.
But is this proved? where are the references?
$\mathrm{CSL}=\mathrm{NSPACE}(O(n))$. Thus, take your favourite PSPACE-complete problem. If it is decidable in $\mathrm{NSPACE}(O(n))$ (for example, QBF is), you are done. Otherwise, introduce a polynomial amount of padding to make it so.