1. On ribbon 2-knots – the 3-manifold bounded by the 2-knots;Yanagawa;Osaka J. Math.,1969
2. [7] Trace B. . A note concerning the 3-manifolds which span certain surfaces in the 4-ball (To appear).
3. [6] Trace B. . Some comments concerning Levine's approach to slicing classical knots (To appear).
4. Doubly slice knots and the Casson-Gordon invariants