(a) Spin-wave dispersion in La2CuO4 along high-symmetry directions in the 2D Brillouin zone, as indicated in (c); T=10 K (295 K): open (filled) symbols. Solid (dashed) line is a fit to the 10 K (295K) data. (b) Spin-wave intensity vs. wave vector. Line is prediction of linear spin-wave theory. From Coldea {\it et al.}