Unamba, Norbert Ndubuisi, Julius Uguru Edeogu, and Miriam Ijeoma Orji. 2020. “The Functional Class and Electrocardiographic Abnormalities in Heart Failure Patients in Southern Nigeria: A Retrospective Observational Study”. The Nigerian Health Journal 20 (2):44-53. https://tnhjph.com/index.php/tnhj/article/view/475.