M.A. Subramanian, C.C. Torardi, J. Gopalakrishnan, P.L. Gai, et al., "Bulk superconductivity up to 122øK in the Tl-Pb-Sr-Ca-Cu-O system," Science, 242, 249-52, 14 October 1988.
Mas Subramanian (E.I. Du Pont de Nemours and Co., Wilmington, Del.): "This is the first paper to report superconductivity in the system Tl-Pb-Sr-Ca-Cu-O with transition temperatures up to 122øK. It also reported the precise structural and compositional information of the 122øK superconductor derived from high resolution microscopic and single crystal X-ray diffraction investigations.
"This paper attracted much attention because high-temperature superconductors with transition temperatures as high as 125øK were known in the system Tl-Ba-Ca-Cu-O but not in the Tl-Sr-Ca-Cu-O system. The work demonstrated how one could stabilize new superconductors by appropriate chemical substitution. It is now recognized that such substitutions not only favor the phase stability, but also may alter the electronic structure, which may induce superconductivity."