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[2] Kyle S. Wiley et al. Maternal distress, DNA methylation, and fetal programing of stress physiology in Brazilian mother–infant pairs. Dev Psychobiol. 2023 Jan;65(1):e22352.
István Péterfi, Lóránd Kellényi, Lehel Péterfi & András Szilágyi (2017): The short-term effect of smoking on fetal ECG, The Journal of Maternal-Fetal & Neonatal Medicine, DOI: 10.1080/14767058.2017.1390560

[3] István Péterfi, Lóránd Kellényi, Lehel Péterfi & András Szilágyi (2017): The short-term effect of smoking on fetal ECG, The Journal of Maternal-Fetal & Neonatal Medicine, DOI:  10.1080/14767058.2017.1390560