Citation: Ming-Liang Tong; Hong-Ji Chen; Xiao-Ming Chen (2000). Molecular Ladders with Multiple Interpenetration of the Lateral Arms into the Squares of Adjacent Ladders Observed for [M2(4,4'-bpy)3(H2O)2(phba)2](NO3)2.4H2O (M = Cu2+ or Co2+; 4,4'-bpy = 4,4'-Bipyridine; phba = 4-Hydroxybenzoate). Inorganic Chemistry, 39, pp. 2235-2238.