   TYPE
     lot$linkage_tree = record
       root: ^lot$linkage_tree_node,
       container: ^SEQ (*),
     recend,

     lot$linkage_tree_node = record
       linkage_info: lot$linkage_name_lists,
       balance: lot$node_balance_factor,
       less,
       greater: ^lot$linkage_tree_node,
     recend,

     lot$node_balance_factor = (loc$balanced, loc$weighted_less, loc$weighted_greater);


