@article{10_4153_CJM_1968_137_4,
     author = {Ton, Bui An},
     title = {Non-Local {Elliptic} {Boundary-Value} {Problems}},
     journal = {Canadian journal of mathematics},
     pages = {1365--1382},
     year = {1968},
     volume = {20},
     number = {1},
     doi = {10.4153/CJM-1968-137-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-137-4/}
}