6Carino Nicholas J. The Impact-Echo Method: An Overview [ EB/OL ]. http://fire. nist. gov/bfrlpubs/build01/PDF/b01005. pdf.
7Cheng CC, Yu CP. An investigation of the transfer function of the impact-echo response and its application[A]. 15th WCNDT[M/CD]. Rome:2000.
8Vincent Gamier, Gilles Comeloup. Non-Destructive Evaluation of Concrete Damage by Ultrasounds[A].15th WCNDT[M/CD]. Rome. 2000.
9Legendre S, Goyette J, Massicotte D. Ultrasonic NDE of composite material structures using wavelet coefficient[J]. NDTb-E International, 2001,34 :31 - 37.