共 74 条
[3]
Beranek L. L., 1949, ACOUSTIC MEASUREMENT
[4]
BESTERMAN EMM, 1953, BRIT HEART J, V15, P130
[5]
Butterworth JS, 1955, CARDIAC AUSCULTATION
[6]
COWEN ED, 1947, BRIT HEART J, V11, P356
[7]
DeForest L., 1908, U.S. Patent, Patent No. [879,532, 879532]