Geometry & Topology Volume 5, issue 2 (2001)

1	M Boileau, J P Otal, Sur les scindements de Heegaard du tore $T^3$, J. Differential Geom. 32 (1990) 209 MR1064873
2	A J Casson, C M Gordon, Reducing Heegaard splittings, Topology Appl. 27 (1987) 275 MR918537
3	M Culler, C M Gordon, J Luecke, P B Shalen, Dehn surgery on knots, Ann. of Math. $(2)$ 125 (1987) 237 MR881270
4	H Doll, A generalized bridge number for links in 3–manifolds, Math. Ann. 294 (1992) 701 MR1190452
5	C Frohman, The topological uniqueness of triply periodic minimal surfaces in $\mathbb{R}^3$, J. Differential Geom. 31 (1990) 277 MR1030674
6	H Goda, M Scharlemann, A Thompson, Levelling an unknotting tunnel, Geom. Topol. 4 (2000) 243 MR1778174
7	Y Hagiwara, Reidemeister–Singer distance for unknotting tunnels of a knot, Kobe J. Math. 11 (1994) 89 MR1309994
8	W Haken, Some results on surfaces in 3–manifolds, from: "Studies in Modern Topology", Math. Assoc. Amer. (distributed by Prentice-Hall, Englewood Cliffs, N.J.) (1968) 39 MR0224071
9	D J Heath, Heegaard splittings of the Figure-8 knot complement are standard, preprint
10	J Hempel, 3–Manifolds, Ann. of Math. Studies 86, Princeton University Press (1976) MR0415619
11	W Jaco, Lectures on three-manifold topology, CBMS Regional Conference Series in Mathematics 43, American Mathematical Society (1980) MR565450
12	P K Kim, J L Tollefson, Splitting the PL involutions of nonprime 3–manifolds, Michigan Math. J. 27 (1980) 259 MR584691
13	T Kobayashi, Classification of unknotting tunnels for two bridge knots, from: "Proceedings of the Kirbyfest (Berkeley, CA, 1998)", Geom. Topol. Monogr. 2, Geom. Topol. Publ., Coventry (1999) 259 MR1734412
14	T Kobayashi, O Saeki, The Rubinstein–Scharlemann graphic of a 3–manifold as the discriminant set of a stable map, Pacific J. Math. 195 (2000) 101 MR1781617
15	K Morimoto, A note on unknotting tunnels for 2–bridge knots, Bull. Fac. Eng. Takushoku Univ. 3 (1992) 219
16	K Morimoto, Tunnel number, connected sum and meridional essential surfaces, Topology 39 (2000) 469 MR1746903
17	H Rubinstein, M Scharlemann, Comparing Heegaard splittings of non-Haken 3–manifolds, Topology 35 (1996) 1005 MR1404921
18	M Scharlemann, A Thompson, Heegaard splittings of $(\mathrm{surface}){\times}I$ are standard, Math. Ann. 295 (1993) 549 MR1204837
19	J Schultens, Additivity of tunnel number for small knots, Comment. Math. Helv. 75 (2000) 353 MR1793793
20	J Schultens, The classification of Heegaard splittings for (compact orientable surface)${\times}S^1$, Proc. London Math. Soc. $(3)$ 67 (1993) 425 MR1226608
21	F Waldhausen, Heegaard-Zerlegungen der 3–Sphäre, Topology 7 (1968) 195 MR0227992