TY  - RPRT
TI  - The Dirichlet Problem for Linear Elliptic Equations of Arbitrary Even Order with Variable Coefficients.
AU  - F E Browder
PY  - 1952
DO  - 10.1073/pnas.38.3.230
UR  - https://pubmed.ncbi.nlm.nih.gov/16589084/
ID  - 16589084
ER  -