1. Land Cover Database v5.0, Mainland, New Zealand. Landcare Research New Zealand. Downloaded from https://lris.scinfo.org.nz/layer/104400-lcdb-v50-land-cover-database-version-50-mainland-new-zealand/.
2. Ballantine D, Booker D, Unwin M, Snelder T. 2010. Analysis of national river water quality data for the period 1998-2007. Prepared for the Ministry for the Environment by NIWA, Client Report CHC2010-38.
3. Water quality trends in New Zealand rivers: 1989–2009
4. New Zealand estuary benthic health indicators summarised nationally and by estuary type
5. Brooking T. 2006. Pasture, present and future – A brief history of pastoralism in New Zealand. MAF RM Update Issue 18. Produced by the Ministry of Agriculture and Forestry. ISSN: 1174-8869.