DOBSON, Michael - FRID, Chris. Ecology of aquatic systems. 2nd ed. Oxford ; New York : Oxford University Press, 2009. xi, 321 s. Available on Internet: <http://www.loc.gov/catdir/enhancements/fy0907/2008036480-d.html> <http://www.loc.gov/catdir/enhancements/fy0907/2008036480-t.html> ISBN 978-0-19-929754-2.