TY  - BOOK
AU  - Sommerville,Duncan M'Laren Young
TI  - The elements on non-Euclidean geometry
U1  - 513.8 
PY  - 1958///
CY  - New York
PB  - Dover Pub.
KW  - Geometry, Non-Euclidean
KW  - Geometry
KW  - Hyperbolic
KW  - Mathematics
ER  -