TY  - RPRT
TI  - The numerical solution of a nonseparable elliptic partial differential equation by preconditioned conjugate gradients 
AU  - Lewis, John Gregg
AU  - Rehm, Ronald G
PY  - 1980
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS IR 80-2056
DO  - 10.6028/NBS.IR.80-2056
ER  -