Me pēnei te tohu i te whārangi:
Mark Derby, 'Ngā whakaahua, ngā rauemi katoa', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/inventions-patents-and-trademarks/media (accessed 30 September 2023)
He kōrero nā Mark Derby, i tāngia i te 11 Mar 2010, updated 1 Feb 2015