TY  - RPRT
TI  - Ruler for measuring physiological tracings with a variable standard.
AU  - D Pickering
PY  - 1975
DO  - 10.1016/s0140-6736(75)91366-5
UR  - https://pubmed.ncbi.nlm.nih.gov/47427/
ID  - 47427
ER  -