public void Add(DateTime date)
        {
            var p = new NodeZbW(date)
            {
                Next = _head
            };

            _head = p;
        }
        protected NodeZbW(SerializationInfo info, StreamingContext context)
        {
            var year  = (int)info.GetValue("year", typeof(int));
            var month = (int)info.GetValue("month", typeof(int));
            var day   = (int)info.GetValue("day", typeof(int));

            Date = new DateTime(year, month, day);
            Next = (NodeZbW)info.GetValue("next", typeof(NodeZbW));
        }