Me pēnei te tohu i te whārangi:
Roger Gregg and Carl Walrond, 'Ngā whakaahua, ngā rauemi katoa', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/oil-and-gas/media (accessed 8 June 2023)
He kōrero nā Roger Gregg and Carl Walrond, i tāngia i te 12 Jun 2006