TY  - RPRT
TI  - Pulse frequency meter.
AU  - W LAWTON
AU  - N L WULFSOHN
PY  - 1958
DO  - 10.1111/j.1365-2044.1958.tb08110.x
UR  - https://pubmed.ncbi.nlm.nih.gov/13545561/
ID  - 13545561
ER  -