TY  - GEN
AU  - Hall,H.S.
AU  - Knight,S.R.
TI  - Elementary trigonometry 
U1  - 514 
PY  - 1962///
CY  - London
PB  - Macmillan & Company
KW  - Geometry
KW  - Distance formula
KW  - Radian measure
ER  -