@article{10_4153_CJM_1972_092_2,
     author = {Stewart, James},
     title = {Counterexample to a {Conjecture} on {Positive} {Definite} {Functions}},
     journal = {Canadian journal of mathematics},
     pages = {926--929},
     year = {1972},
     volume = {24},
     number = {5},
     doi = {10.4153/CJM-1972-092-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1972-092-2/}
}