EN
We present preliminary studies of magnetic and transport properties of Ge_{1-x-y}Sn_xMn_yTe mixed crystals with 0.091 ≤ x ≤ 0.105 and 0.012 ≤ y ≤ 0.115. Qualitative analysis of our experimental results showed the appearance of a spin-glass phase at T < 50 K. The transport characterization (resistivity and Hall effect measurements) showed that the investigated samples had semimetallic p-type conductivity with relatively large carrier concentrations (p > 10^{21} cm^{-3}) and low mobilities (μ < 100 cm^2 V^{-1} s^{-1}). The dependence of transport properties on the chemical composition of the samples was observed.