1. Brummelte S, Grunau RE, Chau V, Poskitt KJ, Brant R, Vinall J, et al. Procedural pain and brain development in premature newborns. Ann Neurol. 2012; 71(3):385-96.
2. Verklan MT, Walden M. Core Curriculum for neonatal intensive care nursing-e-book. Amsterdam: Elsevier Health Sciences; 2014.
3. Kapellou O. Blood sampling in infants (reducing pain and morbidity). BMJ Clin Evid. 2011; 2011:313.
4. MacDonald MG, Ramasethu J, Rais-Bahrami K. Atlas of procedures in neonatology. Philadelpheia: Lippincott Williams & Wilkins; 2012. P. 84-8.
5. Stevens BJ, Abbott LK, Yamada J, Harrison D, Stinson J, Taddio A, et al. Epidemiology and management of painful procedures in children in Canadian hospitals. CMAJ. 2011; 183(7):E403-10.
6. Linda J. Van marter, Pryor CC. Management of pain and stress in the NICU. Manual of neonatal care. 5th ed. Philadelphia: Lippincott Williams & Wilkins; 2004. P. 703-15.
7. Lucas-Thompson R, Townsend EL, Gunnar MR, Georgieff MK, Guiang SF, Ciffuentes RF, et al. Developmental changes in the responses of preterm infants to a painful stressor. Infant Behav Dev. 2008; 31(4):614-23.
8. Hockenberry MJ, Wilson D, Rodgers CC. Wong's essentials of pediatric nursing-e-book. Amsterdam: Elsevier Health Sciences; 2016. P. 228-32.
9. Walden M, Carrier C. The ten commandments of pain assessment and management in preterm neonates. Crit Care Nurs Clin North Am. 2009; 21(2):235-52.
10. de Jesus JA, Tristao RM, Storm H, da Rocha AF, Campos D Jr. Heart rate, oxygen saturation, and skin conductance: a comparison study of acute pain in Brazilian newborns. Conf Proc IEEE Eng Med Biol Soc. 2011; 2011:1875-9.
11. Padhye NS, Williams AL, Khattak AZ, Lasky RE. Heart rate variability in response to pain stimulus in VLBW infants followed longitudinally during NICU stay. Dev Psychobiol. 2009; 51(8):638-49.
12. Reyhani T, Mohebi T, Boskabadi H, Gholami H. The effect of facilitated tucking during venipuncture on pain and physiological parameters in preterm infants. Evid Based Care. 2012; 2(2):47-56.
13. Fatemian S, Mamdouh N, Rouhani K, Ashk TT. Relation between blood sampling pain and heart rate of newborns at fatemieh hospital in hamedan. Facul Nurs Midwifery Quart. 2006; 16(52):48-55. 14. Valeri BO, Holsti L, Linhares MB. Neonatal pain and developmental outcomes in children born preterm: a systematic review. Clin J Pain. 2015; 31(4):355-62.
15. Kattwinkel J, Boyle RJ, Chisholm CA, Clarke SB. PCEP perinatal continuing education program: specialized newborn care. 2nd ed. New York: American Academy of Pediatrics; 2012.
16. Solimano A, Ling E, O'Flaherty D. ACORN acute care of at-risk newborns: a resource and learning tool for health care professionals. Vancouver: ACORN Editorial Board; 2010.
17. Bartocci M, Bergqvist LL, Lagercrantz H, Anand KJ. Pain activates cortical areas in the preterm newborn brain. Pain. 2006; 122(1-2):109-17.
18. Evans JC, McCartney EM, Lawhon G, Galloway J. Longitudinal comparison of preterm pain responses to repeated heelsticks. Pediatr Nurs. 2005; 31(3):216-21.
19. Anand K, Aranda JV, Berde CB, Buckman S, Capparelli EV, Carlo WA, et al. Analgesia and anesthesia for neonates: study design and ethical issues. Clin Ther. 2005; 27(6):814-43.
20. Chimello JT, Gaspardo CM, Cugler TS, Martinez FE, Linhares MB. Pain reactivity and recovery in preterm neonates: latency, magnitude, and duration of behavioral responses. Early Hum Dev. 2009; 85(5):313-8.
21. Holsti L, Grunau RE, Whifield MF, Oberlander TF, Lindh V. Behavioral responses to pain are heightened after clustered care in preterm infants born between 30 and 32 weeks gestational age. Clin J Pain. 2006; 22(9):757-64.
22. Badr LK, Abdallah B, Hawari M, Sidani S, Kassar M, Nakad P, et al. Determinants of premature infant pain responses to heel sticks. Pediatr Nurs. 2010; 36(3):129-36.
23. Manuprakash SK, Varadarajshenoy KK. Comparison of pain response to heel prick and venepuncture in term babies. Indian J Public Health Res Dev. 2012; 3(3):80-4.
24. Mirzarahimi M, Mehrnoush N, Shahizadeh S, Samadi N, Amani F. Effect of non-nutritive sucking and leg massage on physiological and behavioral indicators of pain following heel blood sampling in term neonates. Int J Adv Nurs Stud. 2013; 2(2):74.
25. Shrestha M, Adhikari RK. Comparison of pain response to venepuncture versus heel lance blood sampling in term neonates. J Nepal Paediatr Soc. 2012; 32(2):99-104.
26. Schlueter MA, Johnson BB, Sudman DA, Wang LY, Namkung P, Heasley SV, et al. Blood sampling from scalp arteries in infants. Pediatrics. 1973; 51(1):120-2.
27. Peihua J, She Y, Zhang M. The exploration for blood sampling through children's scalp artery trocar retaining. J Nurses Train. 2002; 1:7.