I.-A. Howard, D. Busko, G. Gao, P. Wendler, E. Madirov, A. Turshatov, J. Moesslein, B.-S. Richards (2024): "Sorting plastics waste for a circular economy: Perspectives for lanthanide luminescent markers" Resources, Conservation & Recycling, Volume 205, June 2024, 107557 https://www.sciencedirect.com/science/article/pii/S0921344924001526?ref=pdf_download&fr=RR-2&rr=86b62387bd1fb39e