6C. Le Gal La Salle. Renewal rate estimation of groundwater based on radioactive traces ( ^3H, ^14C) in an unconfined aquifer in a semi - arid area, Iullemeden Basin,Niger[ J]. Journal of Hydrology, 2001,254( 1 -4) : 145 - 156.
7lan Clark and Peter Fritz. Environmental Isotopes in Hydrogeology Springer[ M] . New York:Lewis Publisher, 1997,171 -195.
