Ratnawati, Diana, et al. “Detection of Newcastle Disease Egg Yolk Titer and Phenotypic Correlation in IPB-D2 Chickens”. The Journal of Poultry Sciences and Avian Diseases, vol. 2, no. 2, Apr. 2024, pp. 56-60, https://doi.org/10.61838/kman.jpsad.2.2.7.