“The Effect of Tegal and Magelang Ducks Cross Types on Production, Shell Thickness and Egg Specific Gravity”. ANGON: Journal of Animal Science and Technology 3, no. 1 (March 15, 2021): 55–65. Accessed October 31, 2025. https://jnp.fapet.unsoed.ac.id/index.php/angon/article/view/181.