This is quite interesting: while the webpage itself is obviously unreliable, the actual document being cited doesn't appear to have been produced by the same people responsible for the page; rather, judging by the formatting and citations, it seems to be a chapter from a book or a journal article of some sort that has merely been uploaded there.  Unfortunately, I don't have the expertise to determine whether Lopukhovsky/Kavalerchik are a reliable source in their own right; while they certainly don't have the name recognition that Krivosheev does, they have written what appear to be actual, non-self-published books (e.g. http://www.ozon.ru/context/detail/id/5440123/), and may thus be a legitimate alternative viewpoint to be considered.
My suggestion would be to ask for assistance on evaluating these authors at WT:MILHIST and/or WP:RSN; perhaps someone who edits more on this topic will have more insight into whether they're serious historians.  [talk]