> Among them, Soviet specialists Michael Ellman and J. Arch Getty have criticized the estimates for relying on émigre sources, hearsay, and rumor as evidence,[36] and cautioned that historians should instead utilize archive material.[37] Such scholars distinguish between historians who base their research on archive materials, and those whose estimates are based on witnesses evidence and other data that is unreliable.[38] Soviet specialist Stephen G. Wheatcroft says that historians relied on Solzhenitsyn to support their higher estimates but research in the state archives vindicated the lower estimates, while adding that the popular press has continued to include serious errors that should not be cited, or relied on, in academia. "Don't listen to the people who escaped genocide. Just read our official records about it."