@article{MZM_1987_42_4_a5,
     author = {A. A. Kosmodem'yanskii (Jr.)},
     title = {Sufficient conditions for the concavity of the solution of the dirichlet problem for the equation $\Delta u=-1$},
     journal = {Matemati\v{c}eskie zametki},
     pages = {537--542},
     publisher = {mathdoc},
     volume = {42},
     number = {4},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1987_42_4_a5/}
}