M. Matuchova, K. Zdansky, J. Zavadil, A. Danilewsky, F. Riesz, M.A.S. Hassan, D. Alexiew, R. Kral (2009): Study of the influence of the rare-earth elements on the properties of lead iodide. Journal of Crystal Growth, volume 311, issue 14, pages 3557–3562. doi:10.1016/j.jcrysgro.2009.04.043