Hervoches, C., Sneddon, A., Riggs, R., Kilcoyne, S., Manuel, P., & Lightfoot, P. (2002). Structural behavior of the four-layer aurivillius-phase ferroelectrics SrBi4Ti4O15 and Bi5T i3FeO15. Journal of Solid State Chemistry, 164(2), 280-291. https://doi.org/10.1006/jssc.2001.9473