@article{CMUC_1980__21_4_a6,
     author = {Gregor, Ji\v{r}{\'\i}},
     title = {Integral representation of $n$-variable positive real functions},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {707--717},
     publisher = {mathdoc},
     volume = {21},
     number = {4},
     year = {1980},
     mrnumber = {597760},
     zbl = {0458.32001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1980__21_4_a6/}
}