Me pēnei te tohu i te whārangi:

Ian McGibbon. Related biographies for 'Duigan, John Evelyn', Dictionary of New Zealand Biography, first published in 1998. Te Ara - the Encyclopedia of New Zealand, https://teara.govt.nz/mi/biographies/4d24/duigan-john-evelyn/related-biographies (accessed 19 April 2024)