S. Lange, C. E. Hartwig, O. Er-Raji, P. S. C. Schulze, M. Turek, and J. Borchert, “Characterization of Ultrathin Layers in Perovskite/TOPCon Tandem Cells With Photoelectron Spectroscopy Utilizing Advanced Data Evaluation Methods”, SiliconPV Conf Proc, vol. 2, Dec. 2024.