International Registry of Evapotranspiration Measurements: This registry does not contain any actual data, but is intended to provide users with information describing the type of evapotranspiration measurements, method used, period of measurements, vegetation type, and the data availability and cost. This web site and organizations do not entertain any responsibility for the correctness of information contained in this registry nor for the accuracy or reliability of any data that are described.

NRCS Irrigation Page: Various irrigation and water management links developed by Tom Spofford with USDA Natural Resource Conservation Service.

IRRISOFT - World Database on IRRIGATION and HYDROLOGY SOFTWARE: IRRISOFT is an Irrigation and Hydrology Software Database which provides information on irrigation and hydrology software and links to servers containing the software packages and further information. Numerous irrigation programs have been written by individuals or groups and are available as public domain, shareware or commercial software. Maintained by Dr.Thomas-M. Stein.

Virtual Land and Water Resources Centre: United Nations Food and Agriculture Organization's Land and Water Resources Information System - Decision Support Software.