1. human embryology part 1;collin,1969
2. diffraction effects in pulse-echo measurement.;fink;ieee trans. sonics ultrason.,1984
3. a book providing a brief introduction to ultrasound imaging, diffraction, and scattering;jensen,1996
4. a general reference on arrays and medical imaging;macovski,1983
5. a general engineering reference on arrays;sternberg,1976