1. The interpretation of the U wave of the electrocardiogram;Nahum;Am Heart J,1939
2. Negative U wave: clinical significance and possible mechanism;Kishida;Circulation,1978
3. XV. U wave in coronary disease;Papp;Circulation,1957
4. Onde U negative a valeur diagnostique et pronostique;Ameur-Hedrich;Ann Cardiol Angeiol (Paris),1976
5. Statistics at square one;Swinscow,1978