Mokhonko , A. A., and A. Z. Mokhonko. “On Meromorphic Solutions to the Systems of Linear Differential Equations With Meromorphic Coefficients”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, no. 1, Jan. 2022, pp. 99 - 112, doi:10.37863/umzh.v74i1.220.