@Article{adams,
    author = {Adams, J. F.},
    title = {Non-existence of elements of Hopf invariant one},
    journal = {Annals of Mathematics},
    volume = {72},
    number = {1},
    pages = {20-104},
    year = {1960},
}

@Article{bott,
    author = {Bott, R. and Milnor, J.},
    title = {On the parallelizability of spheres},
    journal = {Bull. Amer. Math. Soc.},
    volume = {64},
    pages = {87-89},
    year = {1958},
}

@Article{Ch,
    author = {Chern, S. S.},
    title = {Characteristic classes of Hermitian manifolds},
    journal = {Annals of Mathematics},
    volume = {47},
    number = {1},
    pages = {85-121},
    year = {1946},
}

@Article{GIN,
    author = {{Gilkey}, P. B., and Ivanova, R. and Nikcevic, S.},
    title = {Characteristic classes},
    journal = {Elsevier},
    year = {2006},
}


@Book{hatcher,
    author = {Hatcher, A.},
    title = {Vector bundles and K-theory},
    publisher = {book project, http://www.math.cornell.edu/~hatcher/VBKT/VB.pdf},
    year = {2009},
}

@Article{kervaire,
    author = {Kervaire, M.},
    title = {Non-parallelizability of the n-sphere for $n>7$},
    journal = {Proc. Nat. Acad. Sci., U.S.A.},
    volume = {44},
    pages = {280-283},
    year = {1958},
}

@Book{kirk,
    publisher = {AMS Graduate studies in mathematics},
    author = {Davis, J. F. and Kirk, P.},
    title = {Lecture notes in algebraic topology},
    volume = {35},
    year = {2001},
}



@Article{massey,
    author = {Massey, W. S.},
    title = {On the normal bundle of a sphere imbedded in Euclidean space},
    journal = {Annals of Mathematics},
    volume = {10},
    number = {6},
    pages = {959-964},
    year = {1959},
}

@Book{milnor,
    publisher = {Princeton University Press},
    author = {Milnor, J. W. and Stasheff, J. D.},
    title = {Characteristic classes},
    year = {1974},
}

@Article{pontrjagin,
    author = {Pontrjagin, L. S.},
    title = {Characteristic cycles on differentiable manifolds},
    journal = {Mat. Sbornik N. S.},
    volume = {21(63)},
    number = {2},
    pages = {233-284},
    year = {1947},
}

@Book{rotman,
    Publisher = {Springer-Verlag New York Berlin Heidelberg},
    author = {Rotman, J. J.},
    title = {An introduction to algebraic topology},
    year = {1988},
}

@Book{spainer,
    Publisher = {McGraw-Hill},
    author = {Spainer, E. H.},
    title = {Algebraic topology},
    year = {1966},
}

@Book{steenrod,
    Publisher = {Princeton},
    author = {Steenrod, N.},
    title = {The topology of fibre bundles},
    year = {1951},
}

@Book{eps,
    publisher = {Princeton University Press},
    author = {Steenrod, N. and Epstein, D.},
    title = {Cohomology operations},
    year = {1962},
}


@Article{stiefel,
    author = {Stiefel, E.},
    title = {Richtungsfelder und fernparallelismus in mannigfaltigkeiten},
    journal = {Comm. Math. Helv.},
    volume = {8},
    pages = {3-51},
    year = {1936},
}


@Book{stong,
    publisher = {Princeton Univ. Press},
    author = {Stong, R. E.},
    title = {Notes on cobordism theory},
    journal = {Princeton Math. Notes},
    year = {1958},
}

@Book{switzer,
    Publisher = {Springer-Verlag Berlin Heidelberg},
    author = {Switzer, R. M.},
    title = {Algebraic topology, homology and homotopy},
    year = {2002},
}

@Article{whitehead,
    author = {Whitehead, J. H. C.},
    title = {Manifolds with transverse fields in Euclidean space},
    journal = {Annals of Mathematics},
    volume = {73},
    number = {1},
    pages = {154-212},
    year = {1961},
}

@Article{whitney,
    author = {Whitney, H.},
    title = {The ingularities of a smooth n-manifold in (2n-1)-space},
    journal = {Annals of Mathematics},
    volume = {45},
    number = {2},
    pages = {247-293},
    year = {1944},
}
