Arlina, Firda, et al. “Activity and Crowing Frequency of Ayam Kokok Balenggek from West Sumatra by Using and Without Perch”. Journal of Advanced Veterinary Research, vol. 15, no. 6, Nov. 2025, pp. 767-70, https://www.advetresearch.com/index.php/AVR/article/view/2378.