TY  - BOOK
AU  - Butler,Charles H.
AU  - Wren,Frank Lynwood
TI  - Trigonometry for secondary schools: plane and spherical
AV  - QA 531 .B96 1957
U1  - 514 
PY  - 1957///]
CY  - [Boston]
PB  - D. C. Heath
KW  - Trigonometry
ER  -