1. AN IMPROVED METHOD OF FETAL CEPHALOMETRY BY ULTRASOUND
2. ULTRASONICS IN OBSTETRICS
3. W. J. Garrett, and D. E. Robinson (1970 ): Ultrasound in Clinical Obstetrics . Charles C. Thomas, Springfield, Illinois, p47 .
4. Assessment of Fetal Size and Growth Rate by Ultrasonic Echoscopy
5. J. Morrison (1969 ): Proceedings of the 8th International Conference of Medical and Biological Engineering , Chicago Session, 32 , 4 .