Auzinger, W., Hofstätter, H., Koch, O., & Thalhammer, M. (2015). Defect-based local error estimators for splitting methods, with application to Schrödinger equations, Part III. The nonlinear case. Journal of Computational and Applied Mathematics, 236(10), 182–204. https://doi.org/10.1016/j.cam.2014.06.012