A design for a fountain beside a staircase, a park in the background

A drawing by Oppenord depicting the river god and putto on the left, but omitting the staircase and the landscape, is in the Petithory Collection in the Musée Bonnat, Bayonne (P. Jean-Richard, La donation Jacques Petithory au musée Bonnat, Bayonne, exhib. cat., Paris, Musée du Luxembourg, 1997, no. 181). A red chalk version of the Petithory drawing is in the Nationalmuseum, Stockholm and a further variation of the same composition is in the collection of the Royal Institute of British Architects, London.