G.-S. Wang, H.-H. Liu, L.-S. Li, and J.-W. Wang, “Influence of Ovo Injecting IGF-1 on Weights of Embryo, Heart and Liver of Duck During Hatching Stages”, Int. J. Poult. Sci., vol. 11, no. 12, pp. 756–760, Nov. 2012, doi: 10.3923/ijps.2012.756.760.