Humic acid: comprehensive review of production, structure, characterization and applications. International Journal of Pharma and Biosciences, India, v. 17, n. 1, p. 49–59, 2026. DOI: 10.22376/ijpbs.v17i1.161. Disponível em: https://lapinjournals.com/index.php/ijpbs/article/view/161. Acesso em: 9 may. 2026.