Arie M. Rijke & William A. Jesser 2025. Physical Principles of Water Penetration and Repellency of Porous Surfaces and their Relevance to Feathers. Geography, Earth Science and Environment: Research Highlights Vol. 7. (Mar. 2025), 32–51. DOI:https://doi.org/10.9734/bpi/geserh/v7/4443.