Singular

LIB "realclassify.lib";
ring r = 0, (x,y,z), ds;
poly f = (x2+3y-2z)^2+xyz-(x-y3+x2z3)^3;
list NFR = realclassify(f);
NFR[1];
==> Corank = 2
==> Inertia index = 0
==> Normalform equation of type = D[4]-
==> Normalform equation = x2y-y3
==> Milnor number = 4
==> Modality = 0
==> Determinacy <= 3
==> 
addnondegeneratevariables(NFR[1]);
==> Corank = 2
==> Inertia index = 0
==> Normalform equation of type = D[4]-
==> Normalform equation = z2+x2y-y3
==> Milnor number = 4
==> Modality = 0
==> Determinacy <= 3
==>