D. K. M. H. Wijaya, R. Suntari, and S. Syekhfani, “Effect of Applying Several Types of Foliar Fertilizers on Total N and K Levels in Leaves and Production of Apple (Malus sylvestris Mill.) Rome Beauty Varieties in Batu”, cceria, vol. 16, no. 4, pp. 104–111, Oct. 2022.