Boris Godunov : popular musical drama in four acts with a prologue after Pushkin and Karamzin) / M.P. Moussorgsky ; edited and instrumented by N. A. Rimski-Korsakov with the scene at Vasily Blazhenny Cathedral ; added instrumentation of the scene by M. M. Ippolitov-Ivanov ; present edition prepared by I. Iordan and G. Kirkor.