"WATER RESOURCES ASSESSMENT OF GUYANA"(PDF). US Army Corps of Engineers Mobile District & Topographic Engineering Center. December 1998. Archived(PDF) from the original on 2016-11-24. Retrieved 2020-01-03.
"WATER RESOURCES ASSESSMENT OF GUYANA"(PDF). US Army Corps of Engineers Mobile District & Topographic Engineering Center. December 1998. Archived(PDF) from the original on 2016-11-24. Retrieved 2020-01-03.