Art created by Riis (while he was committed as a mental patient, against his own wishes) at Gaustad Sykehus, disappeared into the possession of employees of the hospital, against the wishes of the artist
according to Ketil Bjørnstad's biography of the artist.[2]
Works
Aftenposten said that the painting Castraktion (castration) from 1957[3] is "counted among his most important".[4] (A copy of the painting was printed in Aftenposten in 2011.[5])