Tindall, J.A., Friedel, M.J, and Kunkel, J.R., in-revision, Unsaturated Zone Hydrology for Environmental Scientists and Engineers (second edition): Prentice-Hall, Englewood Cliffs, New Jersey, 625 p. Adding 3 new chapters: Model calibration and prediction analysis – a state of the art review; Model applications in variably-saturated zone flow and transport; Hydrogeophysical applications)
 

Friedel, M. J., 2006, Predicting probable effects of urbanization on future ecological integrity in the Upper Illinois River Basin, USA. In: Baba, A., Howard, K.W.F., and Gunduz, O. (eds), 2006, Groundwater and Ecosystems, NATO Science Series, IV. Earth and Environmental Sciences – vol. 70, Springer, Dordrecht, The Netherlands, 71-92.
  

Friedel, M.J., 2006.  Reliability in estimating urban groundwater recharge through the vadose zone: managing sustainable development in arid and semiarid regions.  In: Tellam, J.H., Rivett, M.O., and Israfilov, R.G. (eds), Urban groundwater management and sustainability. NATO Science Series, IV. Earth and Environmental Sciences, Springer, Dordrecht, The Netherlands, vol. 74, 169-182.