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• [2] J. W. Milnor, Differentiable structures, Mimeographed Notes, Princeton University, Princeton, N. J., 1961.
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Bibliography

[1]

W. C. Hsiang, and W. Y. Hsiang, Some free differentiable actions of and on -sphere, Quart. J. Math. 15 (1964), 371-374. MR 0173266 (30:3479)

[2]

J. W. Milnor, Differentiable structures, Mimeographed Notes, Princeton University, Princeton, N. J., 1961.

[3]

A. Haefliger, Knotted -spheres in -space, Ann. of Math. 75 (1962), 452-466. MR 0145539 (26:3070)

[4]

S. T. Hu, Homotopy theory, Academic Press, New York, 1959. MR 0106454 (21:5186)

[5]

A. Haefliger, Plongements differentiables de variétés dans variétés, Comment. Math. Helv. 36 (1961), 47-82. MR 0145538 (26:3069)

[6]

N. E. Steenrod, Fibre bundles, Princeton Univ. Press, Princeton, N. J., 1951.

[7]

H. Cartan, Seminaire Cartan, Paris, 1950-1951.

[8]

S. Smale, On the structure of manifolds, Amer. J. Math. 84 (1962), 387-399. MR 0153022 (27:2991)

[9]

M. A. Kervaire and J. W. Milnor, Groups of homotopy spheres. I, Ann. of Math. 77 (1963), 504-537. MR 0148075 (26:5584)

[10]

J. W. Milnor, Differentiable manifolds which are homotopy spheres, Mimeographed Notes, Princeton University, Princeton, N. J., 1958.

[11]

H. Whitney, The self intersection of a smooth -manifold in -space, Ann. of Math. 45 (1944), 220-246. MR 0010274 (5:273g)