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↑"Understanding the Processes of Erosion".mountainnature.com. 2009 [last update]. Archived fromthe original on សីហា 28, 2011. RetrievedAugust 31, 2011.{{cite web}}:Check date values in:|year= (help);More than one of|archivedate= and|archive-date= specified (help);More than one of|archiveurl= and|archive-url= specified (help)
↑"iapws.org".iapws.org. 2000 [last update]. Archived fromthe original on សីហា 8, 2011. RetrievedAugust 31, 2011.{{cite web}}:Check date values in:|year= (help);More than one of|archivedate= and|archive-date= specified (help);More than one of|archiveurl= and|archive-url= specified (help)
↑"Percentage of water". Archived fromthe original on 2013-12-14. Retrieved2012-08-22.{{cite web}}:More than one of|archivedate= and|archive-date= specified (help);More than one of|archiveurl= and|archive-url= specified (help)
↑"Fresh water percentage (2)". Archived fromthe original on 2007-07-15. Retrieved2012-08-22.{{cite web}}:More than one of|archivedate= and|archive-date= specified (help);More than one of|archiveurl= and|archive-url= specified (help)