if ( idLess( n1, ListOfCoincidentNodes.front() )) ListOfCoincidentNodes.push_front( n1 );
else ListOfCoincidentNodes.push_back ( n1 );
ListOfCoincidentNodes.sort( idLess );
if ( idLess( n1, ListOfCoincidentNodes.front() )) ListOfCoincidentNodes.push_front( n1 );
else ListOfCoincidentNodes.push_back ( n1 );
ListOfCoincidentNodes.sort( idLess );