A Google Books search for "positively refuted" yields the following:

A second loop-hole concerns only the alien invaders. It is theoretically possible that the Troy-invaders might have adopted the Gray Minyan Ware technique from the Hellas-invaders in circumstances which include no implication about community of culture. The two parties, though involved in the same great migration, might be racially different, and the Troy-invaders might have moved later than the Hellas-invaders. The former might have settled for a time en route somewhere near the fringes of the latter -- in the region of Macedonia and Chalcidice, perhaps, -- remaining in contact long enough to learn the technique of this ceramic art (and apparently nothing else.) [ANATOLY'S QUOTE GOES HERE] The Aegean shores were invaded in the same era by two peoples sharing a specialized and otherwise unknown technique in pottery: common sense will always insist that the two peoples were kindred in culture, -- that their association was not brief, peripheral, and more or less fortuitous, but protracted and intimate.