#### Volume 6, issue 1 (2006)

Regular homotopy and total curvature II: sphere immersions into $3$–space
 1 T E Cecil, P J Ryan, Tight and taut immersions of manifolds, Research Notes in Mathematics 107, Pitman (Advanced Publishing Program) (1985) MR781126 2 T Ekholm, Regular homotopy and total curvature I: circle immersions into surfaces, Algebr. Geom. Topol. 6 (2006) 459 3 M Gromov, Partial differential relations, Ergebnisse series 9, Springer (1986) MR864505 4 M W Hirsch, Immersions of manifolds, Trans. Amer. Math. Soc. 93 (1959) 242 MR0119214 5 N H Kuiper, Convex immersions of closed surfaces in $E^{3}$. Nonorientable closed surfaces in $E^{3}$ with minimal total absolute Gauss-curvature, Comment. Math. Helv. 35 (1961) 85 MR0124865 6 N H Kuiper, W Meeks III, Total curvature for knotted surfaces, Invent. Math. 77 (1984) 25 MR751130 7 P Li, S T Yau, A new conformal invariant and its applications to the Willmore conjecture and the first eigenvalue of compact surfaces, Invent. Math. 69 (1982) 269 MR674407 8 N Max, T Banchoff, Every sphere eversion has a quadruple point, from: "Contributions to analysis and geometry (Baltimore, Md., 1980)", Johns Hopkins Univ. Press (1981) 191 MR648465 9 S Smale, A classification of immersions of the two-sphere, Trans. Amer. Math. Soc. 90 (1958) 281 MR0104227 10 S Smale, The classification of immersions of spheres in Euclidean spaces, Ann. of Math. $(2)$ 69 (1959) 327 MR0105117