She made them for the Lavazza Calendar 2009.
Despite I got no special paintings as model for this images, I find them very typical in the style of 19th century academic painting.There is the narrative arrangement, the perfect surface, the cool colors and the subjects: a couple on a bridge over the Tiber and Romulus and Remus in the Colosseum.
Sure that Leibovitz got more irony than these academic painters but anyhow it’s a kind of quotation, not of a special painting but of a style.