@article{10_4153_CJM_1968_066_0,
     author = {Greiner, Peter C.},
     title = {Estimates for {General} {Coercive} {Boundary} {Problems} on a {Half-Space} for a {Class} of {Elliptic} {Partial} {Differential} {Operators}},
     journal = {Canadian journal of mathematics},
     pages = {679--697},
     year = {1968},
     volume = {20},
     number = {1},
     doi = {10.4153/CJM-1968-066-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-066-0/}
}