GCH+□_k IMPLIES THE EXISTENCE OF TWO NON-ISOMORPHIC COMPLETE NORMAL ST_(k^+)

Ⅰ. INTRODUCTIONLet ◇ denote the diamond principle, □ the box principle, ST_k a Suslin_k-tree. The report presents a new thorough relation between the above combinatorial principles and the Suslin_k-trees.