1.Cunningham F, Leveno K, Bloom S, Hauth J, Rouse D, Spong C. Williams Obstetrics. 23rd Edition. New York: The Mc Graw Hill Medical publishing; 2010.
2. Midwives TRCo. Evidence Based Guidelines for Midwifery-Led Care in Labor-Assessing Progress in Labor Practice Points. 2012.
3. Dixon L, Foureur M. The vaginal examination during labor: Is it of benefit or harm? New Zealand College of Midwives Journal 2010; 42:21-26.
4. Kordi M, Alijahan R. The Diagnostic Accuracy of External Pelvimetry to Predict Dystocia in Nulliparous Women. Zahedan Journal of Research in Medical Sciences 2012; 14(6):36-38.
5. Hobbs L. Assessing cervical dilatation without VEs. The Practising Midwife 1998; 1(11):34-35.
6. Shepherd A, Cheyne H, Kennedy S, McIntosh C, Styles M, Niven C. The purple line as a measure of labor progress: a longitudinal study. BioMed Central BMC Pregnancy and Childbirth 2010; 10(1):54.
7. Narchi NZ, Camargo J da CS de, Salim NR, Menezes M de O, Bertolino MM. The use of the “purple line” as an auxiliary clinical method for evaluating the active phase of delivery. Rev Bras Saúde Matern Infant 2011; 11(3):313-322.
8. Hamm B, Forstner R, Beinder E. MRI and CT 0f the female pelvise. 1st ed. londan: Spriger publisher; 2007.
9. Liselele H, Boulvain M, Tshibangu K, Meuris S. Maternal Height and External Pelvimetry to Predict Cephalopelvic Disproportion in Nulliparous African Women: a Cohort Study. British Journal of Obstetrics and Gynaecology 2000; 107(1):947-952.
10. Rozenholc A, Ako S, Leke R, Boulvain M. The Diagnostic Accuracy of External Pelvimetry and Maternal Height to Predict Dystocia in Nulliparous Women: A Study in Cameroon. British Journal of Obstetrics and Gynaecology 2007; 114(1):630-635.
11. Alijahan R, Kordi M, Porjavad M, Ebrahimzadeh
S, Mahmoudian A. The Diagnostic Accuracy of Clinical and External Pelvimetry in Prediction of Dystocia in Nulliparous Women. Journal of Shahid Sadoughi University of Medical Sciences 2011; 19(3):398-407.
12. Alijahan R, Kordi M, Pourjavad P, Ebrahimzadeh S. The Diagnostic Accuracy Of Clinical Pelvimetry In Nulliparous Women. The Iranian Journal of Obstetrics, Gynecology and Infertility 2011; 14(6):29-30.
13. Kordi M, Alijahan R, Pourjavad P, Ebrahimzadeh S, Mahmoudian A. The Diagnostic Accuracy of the Combination of Maternal Height and Transvers Diagonal of Michaelis sacral Rhomboid Area to Predict Dystocia in Nulliparous Women. Journal of Birjand University of Medical Sciences 2011; 17(3):174-182.
14. Bryne D, Edmonds D. Clinical method for evaluating progress in first stage of labor. The Lancet 1990; 335: 122.
15. Bergsjo p, Koss ks. Iinterindividual variation in vaginal examination finding during labor. Acta Obstetrics Gynecol Scandanivia. 1982; 61(6):509-510.
16. Buchmann EJ, Libhaber E. Accuracy of cervical assessment in the active phase of labor. British Journal of Obstetrics and Gynaecology 2007; 114(7):833.
17. Tuffnell DJ, Bryce F, Johnson N, RJ. L. Simulation of cervical changes in labor: reproducibility of expert assessment. The Lancet 1989 4; 2 (8671):1089-90.