function PLANopen(){
PLAN=window.open("../pages/stadtplan.html", "zweites", "width=560,height=392,location=no,scrollbars=no,menubar=no,status=no,resizable=yes");}

function IMPopen(){
IMP=window.open("../pages/impressum.html", "drittes", "width=660, height=540,location=no,scrollbars=no,menubar=no,status=no,resizable=yes");}