I cite a scholarly work written by an expert, and you cite some website I can't even access, yet my source is the inaccurate one? This doesn't change the fact, as you stated above, that with the exception of perhaps the Pyandino settlement on the Tunguska, there is still no real evidence that Pyanda made this journey. It's still only people writing a century after the fact, and according to you, Pyanda's journey is almost entirely pure speculation on the part of this Okladnikov fellow. That's not very convincing evidence by any means. And even if the Cossacks knew of the existence of the Lena in 1611-12, that doesn't mean they had reached it at such an early date. Numerous features were known to European explorers in North America before they were ever sighted (Great Salt Lake, most of the Great Lakes, etc.). This still doesn't prove that Pyanda's discoveries ever occured.