1. US Geological Survey 2017 https://water.usgs.gov/edu/earthhowmuch.html
2. FAO 2011 Fisheries and Aquaculture Software FishStatJ http://www.fao.org/fishery/statistics/software/fishstatj/en
3. World Bank 2013
4. Bible http://www.catholic.org/bible/book.php?id=17&bible_chapter=6