Jarulis, J., D. D. Solihin, A. Mardiastuti, L. B. Prasetyo, and W. Novarino. “Morphometric Analysis and Interrelationship of Seven Indonesian Hornbill Species (Aves, Bucerotidae) Utilizing Principal Component and Cluster Analyses”. Zoodiversity, Vol. 58, no. 3, Apr. 2024, doi:10.15407/zoo2024.03.257.