1. Spectrophotometric analysis of amniotic fluid;Crosby;Am. J. Obstet. Gynecol.,1965
2. Intrauterine respiration of the fetus;Davis;J. A. M. A.,1946
3. Fetography;Daw;Am. J. Obstet. Gynecol.,1973
4. Human fetal respiration;Duenhoelter;Obstet. Gynecol.,1973
5. Das intrauterine Fetogram;Erbslöh;Arch. Gynaecol.,1942