Carter, E.P. and Andrus, E.C.: QT interval in human electrocardiogram in absence of cardiac disease. JAMA78: 1922, 1922 .
2.
White, P.D. and Mudd, S.G.: Observations on the effect of various factors on the duration of the electrical systole of the heart as indicated by the length of QT interval of the electrocardiogram . J. Clin. Invest.7: 389, 1929.
3.
Barker, P.S. , Johnson, F.D., and Wilson, F.N.: Duration of systole in hypocalcemia. Amer. Heart J.14: 82, 1937.
4.
Ljung, O.: The electrocardiogram in hypocalcemia with special reference to the T wave . Acta Med. Scandinav.136: 56, 1949.
5.
Bronsky, D., Dubin, A., Waldestein, S.S. and Kushner, D.: Electrocardiographic manifestations of hypoparathyroidism. Amer. J. Cardiol.7: 823, 1961.
6.
Yu, P.N.G. : Electrocardiographic changes associated with hypercalcemia and hypocalcemia. Amer. J. Med. Sci.224: 418, 1952.
7.
Bichtel, J.T. , White, J.E. and Estes, E.H., Jr.: The electrocardiographic effects of hypocalcemia induced in normal subjects with Edathmil disodium . Circulation13-837, 1956.
8.
Bronsky, D., Kusher, D.S., Dubin, A. and Snapper, I.: Idiopathic hypoparathyroidism and pseudohypoparathyroidism: Case report and review of literature. Medicine37: 317, 1958.
9.
Ernstein, J.S. and Proudfit, W.L.: Differentiation of the changes in the QT interval in hypocalcemia and hypopotassemia. Am. Heart J.38: 260, 1949.
10.
Marzahn, H. : Uber eine Veranderung des ST intervalls in Elektrokardiogram bei einem Fall von Postoperativer Tetanie. Ztschr. Klin . Med.127: 182, 1934.
11.
Kleinfeld, M. and Gross, M.: Electrocardiographic manifestations of hypocalcemia produced with ethylene-diamine tetraacetic acid. Amer. J. Physiol.187: 479, 1956.
12.
Bellet, S.: The electrocardiogram in electrolyte imbalance. Arch. Int. Med.96: 618, 1955.
13.
Marzahan, H. : Uber elektrokardiographische veranderungen bei postoperativer tetanie. Deutsche Med. Wehnschr.61: 507, 1936.
14.
Surawicz, B. and Lepschken, E.: The electrocardiographic pattern of hypopotassemia with and without hypocalcemia. Circulation8: 801, 1953.
15.
Surawicz, B. , Lepeschken, E., Herrlich , H.C. and Hoffman, B.F.: Effect of potassium and calcium deficiency on monophasic action potential, electrocardiogram and contractility of isolated rabbit hearts. Amer. J. Physiol.196: 1302, 1959 .
16.
Szekely, P. : The action of magnesium on the heart. Brit. Heart J.8: 115, 1946.
