    class
    	TWO_WAY_LIST [G]

    Ancestors
    	LINKED_LIST [G]
    	LINKED_LIST [G]

    Descendants
    	PART_SORTED_TWO_WAY_LIST [G -> PART_COMPARABLE]
    	SORTED_TWO_WAY_LIST [G -> COMPARABLE]
    	TWO_WAY_TREE [G]

    Clients
    	NDFA*
    	PDFA
    	TWO_WAY_LIST [G]
    	TWO_WAY_TREE [G]

    Suppliers
    	BI_LINKABLE [G]
    	BOOLEAN
    	INTEGER_32
    	TWO_WAY_LIST [G]
    	TWO_WAY_LIST_CURSOR [G]