June 4, 2014 - The 1992 journal article "The equations of reduced magnetohydrodynamics" by G. P. Zank and W. H. Matthaeus was selected as one of 12 classic papers by the Journal of Plasma Physics. The papers were chosen by the journal's editorial board from among all papers published in JPP with more than 100 citations. In their paper, available for free download here, Zank and Matthaeus developed a theoretical framework, called Reduced Magnetohydrodynamics (RMHD), to study plasma with magnetic field in the absence of short scale fluctuations, which provided a simpler, more tractable alternative to the full system of MHD equations for compressible magnetofluids. The RMHD theory has since found applications in solar and space physics, plasma fusion, and turbulence research.