TY  - RPRT
TI  - Characteristic Coordinates for Hyperbolic Differential Equations in the Large.
AU  - T Y Thomas
PY  - 1947
DO  - 10.1073/pnas.33.8.242
UR  - https://pubmed.ncbi.nlm.nih.gov/16578268/
ID  - 16578268
ER  -