“Transform the Multivariate to Unitevariate System and Using Elimination and Duplication Matrices With Some Applications”. Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ), vol. 30, no. 2, Oct. 2021, pp. 35-47, https://doi.org/10.55562/jrucs.v30i2.364.