%0 Journal Article %A J.M Tarascon %A E Wang %A S Kivelson %A B.G Bagley %A G.W Hull %A Ramamoorthy Ramesh %B Physical Review B %D 1990 %G eng %P 218-222 %R 10.1103/PhysRevB.42.218 %T Magnetic versus nonmagnetic ion substitution effects on Tc in the La-Sr-Cu-O and Nd-Ce-Cu-O systems %V 42