Although it is sometimes stated that 'Tibetan singing bowls' date back to a pre-Buddhist, shamanic Bon-Po tradition, the manufacture and use of bowls specifically for the purpose of 'singing' (as opposed to standing bells/bowls that are intended to be struck) is believed to be a modern phenomenon. The historical records and accounts of the music of Tibet are silent about singing bowls. Such bowls are not mentioned by Perceval Landon (a visitor in 1903-1904) in his notes on Tibetan music, nor by any other visitor. Likewise, though ringing and clanging sounds were noted by missionaries interested in traditional Tibetan healing practices, they make no mention of singing bowls. The objects often now referred to as 'Tibetan singing bowls', and marketed as Tibetan ritual instruments, have been called "dharma products" that in fact come from northern India or Nepal, and are neither Tibetan nor ritual in origin.