Studies on the Electrocardiogram of Myocardial Infarction : CONSIDERATIONS ON THE ABNORMAL QRS COMPLEX IN EXPERIMENTAL CORONARY ARTERY EMBOLIZATION : [APPENDIX I] ELECTROCARDIOGRAMS OF S-TYPE IN CLINICAL CASES OF POSTERIOR MYOCARDIAL INFARCTION : [APPENDIX II] INTRODUCTION TO THE ALGEBRAIC REFLECTIONS ON THE VECTOR CONCEPT IN ELECTROCARDIOGRAPHY