TY  - RPRT
TI  - Routines for calculating the first derivative of a function by numerical methods.
AU  - G L Atkins
PY  - 1977
DO  - 10.1016/0010-4825(77)90037-3
UR  - https://pubmed.ncbi.nlm.nih.gov/913088/
ID  - 913088
ER  -