Chez Tortoni was in the museum in Boston until it was stolen on what date?
Chez Tortoni:  The painting hung in the Isabella Stewart Gardner Museum of Boston, Massachusetts, United States, prior to being stolen in 1990. Isabella Stewart Gardner Museum theft: In the early hours of March 18, 1990, guards at the Isabella Stewart Gardner Museum in Boston admitted two men posing as police officers responding to a disturbance call.
March 18, 1990