Azuakemu, C. J., and A. Prince. “Lubricant Automobile Oil: Effect on Chemical and Heavy Metal Status of Soil in Rivers State, South-South, Nigeria”. International Journal of Contemporary Research and Review, vol. 14, no. 03, Mar. 2023, pp. 20231-7, https://ijcrr.info/index.php/ijcrr/article/view/1003.