@article{PORMA_2000__57_4_49016,
     author = {Burger, M.},
     title = {Zonoids and conditionally positive definite functions.},
     journal = {Portugaliae mathematica},
     pages = {443--458},
     publisher = {mathdoc},
     volume = {57},
     number = {4},
     year = {2000},
     zbl = {0977.52005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_2000__57_4_49016/}
}