TY  - BOOK
AU  - Kagan,V.F.
AU  - Katah,B
TI  - N. Lobachevsky and his contribution to science
U1  - 92 
PY  - 1957///
CY  - Moscow
PB  - Foreign Languages Pub. House
KW  - Lobachevsky N.,
KW  - Geometry, Hyperbolic
N1  - Bibliography : p. 88-92
ER  -