Citation: Cui, Feng-Yun; Ma, Xiao-Yu; Li, Cong; Dong, Tao; Gao, Yuan-Zhe; Han, Zhan-Gang; Chi, Ying-Nan; Hu, Chang-Wen (2010). Two new organic--inorganic hybrid compounds based on metal--pyrazine coordination polymers and Keggin polyoxometalates: effect of metal ions on thestructure. Journal of Solid State Chemistry, 183, pp. 2925-2931.