@article{IM_1989__98_1_143719,
     author = {Wu-yi Hsiang and Wu-Teh Hsiang},
     title = {On the uniqueness of isoperimetric solutions and imbedded soap bubbles in non-compact symmetric spaces, {I.}},
     journal = {Inventiones mathematicae},
     pages = {39--58},
     publisher = {mathdoc},
     volume = {98},
     number = {1},
     year = {1989},
     zbl = {0682.53057},
     url = {http://geodesic.mathdoc.fr/item/IM_1989__98_1_143719/}
}