function showSource( el_id ){
	document.getElementById( el_id ).style.display = 'none';
	document.getElementById( el_id + "-source" ).style.display = 'block';
}

function showMain( el_id ){
	document.getElementById( el_id ).style.display = 'block';
	document.getElementById( el_id + "-source" ).style.display = 'none';
}