TY  - RPRT
TI  - Exercise phonocardiogram: with special reference to Q-II A interval on exercise.
AU  - M Nakayama
PY  - 1971
DO  - 10.1253/jcj.35.12_1551
UR  - https://pubmed.ncbi.nlm.nih.gov/5172475/
ID  - 5172475
ER  -