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3. Birgeneau, R.J., Chen, C.Y., Gabbe, D.R., Jensen, H., Kastner, M.A., Peters, C.J., Picone, P.J., Thio, T., Thurston, T.R., Tuller, H.L.: Phys. Rev. Lett.59, 1329 (1987)
4. Goodenough, J.B.: MRS Bulletin, May 1990, 23
5. Braden, M., Schweiss, P., Heger, G., Reichardt, W., Fisk, Z., Gamayunov, K., Tanaka, I., Kojima, H.: Physica C (submitted for publication)