@article{GDZPPN002088452,
title = {Minimal Total Absolute Curvature for Immersions},
journal = {Inventiones mathematicae},
volume = {11},
year = {1970},
pages = {209-238},
zbl = {0195.51102},
url = {http://dml.mathdoc.fr/item/GDZPPN002088452}
}
KUIPER, N.H. Minimal Total Absolute Curvature for Immersions. Inventiones mathematicae, Tome 11 (1970) pp. 209-238. http://gdmltest.u-ga.fr/item/GDZPPN002088452/