TY  - BOOK
AU  - Iversen Birger
TI  - Hyperbolic geometry
T2  - London Mathematical Society student text; 25
SN  - 0521435285
U1  - B692, N2 
PY  - 1992///
CY  - Cambridge
PB  - Cambridge University press       
KW  -  Geometry
KW  -  Hyperbolic
KW  - Mathematics
ER  -