C. O. Duru, J. M. Chinawa, I. D. Peter, I. Aliyu, and F. Bode-Thomas, “Prevalence of valvar regurgitation in Nigerian children with structurally normal hearts using colour doppler echocardiography”, J Cardiovasc Med Cardiol, vol. 7, no. 3, pp. 262–267, Aug. 2020.