Me pēnei te tohu i te whārangi:
Elizabeth S. Wilson. Related biographies for 'Friström, Clas Edvard', Dictionary of New Zealand Biography, first published in 1996. Te Ara - the Encyclopedia of New Zealand, https://teara.govt.nz/mi/biographies/3f13/fristrom-clas-edvard/related-biographies (accessed 24 April 2024)