@article{JCA_1996_3_1_a10,
     author = {L. Qi and R. S. Womersley},
     title = {On {Extreme} {Singular} {Values} of {Matrix} {Valued} {Functions}},
     journal = {Journal of convex analysis},
     pages = {153--166},
     publisher = {mathdoc},
     volume = {3},
     number = {1},
     year = {1996},
     url = {http://geodesic.mathdoc.fr/item/JCA_1996_3_1_a10/}
}