// Ein- und Ausblenden von Referenzen
function schalter(on, off1, off2, off3, off4, off5) {
if (document.getElementById) {  
document.getElementById(on).style.display = 'block';
document.getElementById(off1).style.display = 'none';
document.getElementById(off2).style.display = 'none';
document.getElementById(off3).style.display = 'none';
document.getElementById(off4).style.display = 'none';
document.getElementById(off5).style.display = 'none';
}
else {
if (document.layers) {  
'document.'+ on +'.display = "block"';
'document.'+ off1 +'.display = "none"';
'document.'+ off2 +'.display = "none"';
'document.'+ off3 +'.display = "none"';
'document.'+ off4 +'.display = "none"';
'document.'+ off5 +'.display = "none"';
}
else { 
on +'.style.display = "block"';
off1 +'.style.display = "none"';
off2 +'.style.display = "none"';
off3 +'.style.display = "none"';
off4 +'.style.display = "none"';
off5 +'.style.display = "none"';
}
}
}