/// <summary>
        /// Puts a new reference into this reference map.
        /// </summary>
        /// <param name="locator">a locator to find the reference by.</param>
        /// <param name="component">a component reference to be added.</param>
        public override void Put(object locator, object component)
        {
            base.Put(locator, component);

            if (_opened)
            {
                Referencer.SetReferencesForOne(ParentReferences, component);
            }
        }