gap> R:=ResolutionPSL2QuadraticIntegers(-11,10);
Resolution of length 10 in characteristic 0 for PSL(2,O-11) . 
No contracting homotopy available. 

gap> Size(R);
[ 12, 59, 89, 107, 125, 230, 208, 270, 326, 515 ]
