APA (7th ed.) Citation

GW, B. (1981). The first heart sound in left bundle branch block: An echophonocardiographic study. Circulation, 63(2), 429. https://doi.org/10.1161/01.cir.63.2.429

Chicago Style (17th ed.) Citation

GW, Burggraf. "The First Heart Sound in Left Bundle Branch Block: An Echophonocardiographic Study." Circulation 63, no. 2 (1981): 429. https://doi.org/10.1161/01.cir.63.2.429.

MLA (9th ed.) Citation

GW, Burggraf. "The First Heart Sound in Left Bundle Branch Block: An Echophonocardiographic Study." Circulation, vol. 63, no. 2, 1981, p. 429, https://doi.org/10.1161/01.cir.63.2.429.