@article{CMH_1971__46_139466,
     author = {Hermann Karcher},
     title = {Pinching {Implies} {Strong} {Pinching}},
     journal = {Commentarii mathematici Helvetici},
     pages = {124--126},
     publisher = {mathdoc},
     volume = {46},
     year = {1971},
     zbl = {0216.43803},
     url = {http://geodesic.mathdoc.fr/item/CMH_1971__46_139466/}
}