'Willem Einthoven devised a way to measure & record its electrical current, thus producing the EKG'
the heart
POTPOURRI: Willem Einthoven devised a way to measure & record its electrical current, thus producing the EKG
Willem Einthoven devised a way to measure & record its electrical current, thus producing the EKG
Willem Einthoven devised a way to measure & record its electrical current, thus producing the EKG
POTPOURRI
the heart
POTPOURRI