A 'long-forgotten' portrait by Amrita Sher-Gil, which was rediscovered recently is going under the hammer at a Christie's auction in New York and it could fetch up to $2.8 million. Titled 'Portrait of Denyse', the oil painting made nearly nine decades ago features Sher-Gil's friend and art critic Denyse Proutaux. The portrait had been in private collections since it was created, according to Christie's.