L. Bouqbis, S. Daoud, H.-W. Koyro, C. Irene Kammann, L. Fatima Zohra Ainlhout, and M. Cherif Harrouni, “Biochar from argan shells: production and characterization”, Int. J. Recycl. Org. Waste Agric., vol. 5, no. 4, Nov. 2016, doi: 10.1007/s40093-016-0146-2.