1. Note sur les dédoublements normaux des bruits du coeur;Potain;Bull, et mém. Soc. méd. hôp. Paris,1866
2. Splitting of the second heart sound in health;Leatham;Brit. Heart J.,1951
3. Splitting of the first and second heart sounds;Leatham;Lancet,1954
4. Physiologic splitting of the second heart sound;Boyer;Circulation,1958
5. Cardiovascular Sound in Health and Disease;Boyer,1958