Abstract

References
1.
1.
Kremkau FW
. Diagnostic Sonography: Principles and Instruments . Fourth Edition . Philadelphia : WB Saunders , 1993 .
2.
2.
Kremkau FW
. Attenuation . JDMS
1992 ;8 :100 -102 .
3.
3.
Kremkau FW
. Attenuation II . JDMS
1992 ;8 :211 -212 .
