Unger, W. E. S., Senoner, M., Stockmann, J. M., Fernandez, V., Fairley, N., Passiu, C., Spencer, N. D., & Rossi, A. (2022). summary of ISO/TC 201 International Standard ISO 18516:2019 Surface chemical analysis—Determination of lateral resolution and sharpness in beam‐based methods with a range from nanometres to micrometres and its implementation for imaging laboratory X‐ray photoelectron spectrometers (XPS). Surface and interface analysis, 54, 320–327. http://access.bl.uk/ark:/81055/vdc_100152645067.0x00004f