". . . . the only known instrument possessing his [G. Tononi's] label. An X-ray photograph of the instrument reveals the original nails used to fasten the neck to the top block."
Preservation or incarceration, Pierre Ruhe, The Strad, November, 1997, London
"Although Giovanni Battista Tononi has hitherto been unknown as a member of the chief violinmaking family of Bologna (the others are earlier), all experts who have examined the cello are agreed that the label gives every evidence of being genuine, and there can be no question of the eighteenth century date of the instrument itself, which is preserved in extraordinarily fresh condition."
The Classic Bowed Stringed Instruments from the Smithsonian Institution, The Classic Bowed Stringed Instruments from the Smithsonian Institution, Tokyo