@article{AM2_1993__46_2-3_137555,
     author = {J\"urg R\"atz and Janusz Matkowski},
     title = {On the equality condition in {H\"older's} and {Minkowski} inequalities.},
     journal = {Aequationes mathematicae},
     pages = {220--228},
     year = {1993},
     volume = {46},
     number = {2-3},
     zbl = {0790.26016},
     url = {http://geodesic.mathdoc.fr/item/AM2_1993__46_2-3_137555/}
}