Ibrahim, AA., Vanneste, G., Naveau, H., & Nyns, E.-J. (1981). Possibilities and Limitations of Upgrading Pig Manure Into Animal Feed By Air-lift Fermentation. Revue des Fermentations et des Industries Alimentaires, 36(2), 55-60. https://hdl.handle.net/2078.5/72245 (Original work published 1981)