Clark, S., Segall, M., Pickard, C., Hasnip, P., Probert, M., Refson, K., & Payne, M. (2005). First principles methods using CASTEP. Zeitschrift für Kristallographie - Crystalline Materials, 220(5-6), 567-570. https://doi.org/10.1524/zkri.220.5.567.65075