Some sites erroneously identify this as a portrait of Eilif Peterssen by Christian Krogh. Norway's national museum of art in Oslo, The National Museum of Art, Architecture and Design (Norwegian: Nasjonalmuseet for kunst, arkitektur og design) says it is a self portrait by Eilif Peterssen: http://samling.nasjonalmuseet.no/no/object/NG.M.01578 [sh]