1. Direct-writing heartsound recorder;Rushmer;Amer J Dis Child,1952
2. Variability in detection and interpretation of heart murmurs;Rushmer;Amer J Dis Child,1952
3. Spectral phonocardiography. Problems and prospects in the application of the Bell sound spectrograph to phonocardiography;McKusick;Bull Johns Hopkins Hosp,1954
4. Spectral phonocardiography: clinical studies;McKusick;Bull Johns Hopkins Hosp,1954
5. Quantitative amplitude representation in sound spectrograms (Bell Labs monograph B-1622);Koenig;J Acoust Soc Amer,1948