1. Essential embeddings of annuli and Möbius bands in 3-manifolds;Cannon;Trans. Amer. Math. Soc.,1976
2. Ribbon concordance of knots in the 3-sphere;Gordon;Math. Ann.,1981
3. Some results on surfaces in 3-manifolds;Haken,1968
4. A necessary and sufficient condition for a 3-manifold to hve Heegaard genus one;Hass;Proc. Amer. Math. Soc.,1989
5. 3-Manifolds;Hempel,1976