1. EXTRASYSTOLES ARISING FROM THE MAIN BUNDLE OF HIS
2. SCHERF D. AND SCHOTT A.: Extrasystoles and Allied Arrhythmias. New York Grune and Stratton Inc. 1953.
3. Premature contractions arising in the junctional tissues;'LEWIS T.;Quart. J. MAed.,1911
4. An instance of premature beats arising in the auriculoventricular bundle of a young child;ALLEN H. W.;Am. J. AI. Sc.,1913
5. 'WENCKEBACH K. F. AND WINTERBERG H.: Die unregelmassige Herztatigkeit. Leipsig Engelmann 1927 fig. 138 on plate 57.