procedure search( key : typekey; t : tree );
	begin
	if t=nil then	           {*** Not Found *** }
			notfound( key )
	else if t^.OwnerKey = key then {*** Found *** }
			found( t ^  )
	else if t^.SplitKey < key then	search( key, t^.right )
			else		search( key, t^.left )
	end;