TY  - RPRT
TI  - Keldysh approximation, A2, and strong-field ionization.
AU  - PW Milonni
AU  - JR Ackerhalt
PY  - 1989
DO  - 10.1103/physreva.39.1139
UR  - https://pubmed.ncbi.nlm.nih.gov/9901350/
ID  - 9901350
ER  -