If you find this website is helpful to your teaching and your research, or useful to your middle/high school science project, you could refer this site. Based on the guide lines described by MLA web citation style (MLA Handbook, 7th, 2009),  you can cite this website as follow:

Liu, J.P.,  2011.  Global River and Delta Systems Source-to-Sink References on Google Map. URL: http://www.meas.ncsu.edu/sealevel/s2s/ ,  accessed on yyyy-mm-dd (the date of your access).