“Using Multivariate Gray Model to Predict CO2 Emissions and People Using Safely Managed Sanitation Services”. Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ), vol. 54, no. 1, Jan. 2024, pp. 159-67, https://doi.org/10.55562/jrucs.v54i1.587.