"The long-serving and deserving managing director painter Carl Murdfield, who retired as a result of reaching the age limit, was succeeded by the painter custodian F. Kocks." - Cf. section "Society for the Promotion of Düsseldorf Fine Arts". In Administrative Report of the City of Düsseldorf for the Period from 1 April 1933 to 31 March 1936. Düsseldorf [1937], p. 36 (uni-duesseldorf.de)
