6Plothick G P.Medical management of the patients with unstable angina. The Journal of The American Medical Association . 1978
7Jiang Yi-Qing,Na Shun,et al.Experimental coronary spasm induced coronary thrombosis and myocardial infarction prevented by intravenous nifedipine. Chinese Medical Journal . 1989
8Conti C K,et al.Unstable angina pectoris:Morbidity and mortality in 57 consecutive patients evaluated angiographically. The American Journal of Cardiology . 1973