I see references to George Vernadsky, but no details on which history contained this information, nor how Vernadsky derived the 166lb figure. I am not even sure if he is measuring pre-17th Century Mongolian bows, since post-17th Century, Mongolian bows were influenced by the Manchu designs.

The site the interestingengineering references, itself does not contain references. There are odd discrepancies, such as the section on stringing the bow. Past a certain draw weight, you can no longer string the bow using the one leg or sitting method. The Manchus used equipment off the horse to string their bow, and kept them in cases while strung, to protect them.