[1] [1] Y Y Hung，C E Taylor. Speckle shearing interferometric camera: a tool for measurement of derivatives of surface displacement[J]. Proc. SPIE，1973，41: 169-175.

[7] [7] Y Y Hung，W D Luo, et al. NDT of joined surfaces using digital time-integrated shearography with multiple-frequency sweep[J]. Optics and Lasers in Egineering，2000,33:369-382.

[17] [17] B H Liu, Y WQin, et al. Non-Destructive test of multiply plywood using ESSPI with wide audio-frequency driving vibration[C]// Optical Technology and Processing For Fluids and Solids Diagnostics，(Proceeding of SPIE-The International Society for Optical Engineering)，Beijing, CHINA, 2002,5058:307-311.