Yılmaz, Cansu, et al. “Low Serum IGF-1 and Increased Cytokine Levels in Tracheal Aspirate Samples Are Associated With Bronchopulmonary Dysplasia”. The Turkish Journal of Pediatrics, vol. 59, no. 2, Apr. 2017, pp. 122-9, https://doi.org/10.24953/turkjped.2017.02.003.