Popham suggests that this is an early drawing. The right putto on recto is almost identical to one in a drawing in the British Museum (Popham, op. cit., no. 164) and one on the left of a sheet in the Pierpont Morgan Library (no. 313), both of which are studies for the putti at Fontanellato of circa 1523-4. David Ekserdjian has kindly endorsed the attribution.