Yang, S., Meng, Z., Li, Y., Chen, R., Yang, Y., & Zhao, Z. (2021). “Evaluation of physiological characteristics, soluble sugars, organic acids and volatile compounds in ‘Orin’apples (Malus domestica) at different ripening stages”. Molecules26 (4): 807. doi:10.3390/foods10020274.
Li, Z., Sugaya, S., Gemma, H. & Iwahori, S. (2002). “Flavonoid biosynthesis and accumulation and related enzyme activities in the skin of 'Fuji' and 'Oorin' apples during their development”. Journal of the Japanese Society for Horticultural Science71 (3): 317-321. doi:10.2503/jjshs.71.317.