Our paper, “Strong Photon-Magnon Coupling Using a Lithographically Defined Organic Ferrimagnet,” by Q. Xu, H. F. H. Cheung, D. S. Cormode, T. O. Puel, S. Pal, H. Yusuf, M. Chilcote, M. E. Flatté, E. Johnston-Halperin, and G. D. Fuchs is now out at Advanced Science.