TY  - BOOK
AU  - Echols, William
TI  - An elementary text-book on the differential and integral calculus 
SN  - 1362023432
AV  - QA303  .E34 1902 c.1
PY  - 1902///
CY  - New York 
PB  - Henry Holt and company 
KW  - Calculus
ER  -