1. Vector fields on spheres;Adams;Ann. Math., Princeton,1962
2. Note on cross-sections over CW-complexes;Barcus;Quart. J. Math.,1954
3. Whitehead products and projective spaces;Barratt;J. Math. Mech. Indiana,1960
4. Topologie Generale III;Bourbaki,1961
5. Immersions in the stable range;Haefliger;Ann. Math., Princeton,1962