1. Omoto R, Kasai C, Maekawa K, Kondo Y, Yoshikawa Y, Koyano A, Kyo S, Takamoto S, Yokote Y (1984) Color atlas of real-time two-dimensional Doppler echocardiography. Sindanto-Chiryo, Tokyo
2. DeMaria AN, Smith ND, Kwang OL (1985) Doppler flow imaging; Another step in the evolution of cardiac ultrasound. Echocardiography 2: 495–500
3. Swenson RE, Sahn DJ, Valdes-Cruz LM (1985) Color flow Doppler mapping in congenital heart disease. Echocardiography 2: 545–549
4. White DH, Curry GR (1977) Color-coded differential velocity carotid bifurcation scanner. IEEE T-SU 76: 207–208
5. Bellhouse BJ, Bellhouse HF (1969) Fluid mechanics of the mitral valve. Nature 224: 615–616