Citation: Abrahams, I.; Hawkes, G. E.; Bush, A. J.; Nunes, T. (1999). Structure and Oxide Ion Conductivity Mechanism in Bi~2~Al~4~O~9~ by Combined X-Ray and High-Resolution Neutron pPwder Diffraction and ^27^Al Solid State NMR. Journal of Solid State Chemistry, 147, pp. 631-636.