/// <summary>
        /// Adds a new equivalence class
        /// </summary>
        /// <returns></returns>
        public CMEquivalenceClassUI addEquivalenceClass()
        {
            EquivalenceClass     eq1     = new EquivalenceClass(_elementReal);
            CMEquivalenceClassUI myClass = new CMEquivalenceClassUI(eq1);

            myClass.parentElement = this;
            //if (EquivalentClasses.Count > 1)
            //patch !!!
            EquivalentClasses.Add(myClass);

            return(myClass);
        }
 /// <summary>
 /// Append a new equivalenceClass from
 /// </summary>
 /// <param name="eq"></param>
 public void addEquivalenceClass(CMEquivalenceClassUI eq)
 {
     EquivalentClasses.Add(eq);
     eq.parentElement = this;
 }