"Vermiculture/Vermicompost". Agri.And.Nic.in. Port Blair: Department of Agriculture, Andaman & Nicobar Administration. 18 June 2011. Archived from the original on 17 January 2016. Retrieved 17 April 2009.
González-Pérez, M.; Vidal Torrado, P.; Colnago, L. A.; Martin-Neto, L.; Otero, X. L.; Milori, D. M. B. P.; Haenel Gomes, F. (2008). "13C NMR and FTIR spectroscopy characterization of humic acids in spodosols under tropical rain forest in southeastern Brazil". Geoderma. 146 (3–4): 425–433. Bibcode:2008Geode.146..425G. doi:10.1016/j.geoderma.2008.06.018.
Knicker, H.; Almendros, G.; González-Vila, F. J.; Lüdemann, H. D.; Martin, F. (1995). "13C and 15N NMR analysis of some fungal melanins in comparison with soil organic matter". Organic Geochemistry. 23 (11–12): 1023–1028. Bibcode:1995OrGeo..23.1023K. doi:10.1016/0146-6380(95)00094-1.
González-Pérez, M.; Vidal Torrado, P.; Colnago, L. A.; Martin-Neto, L.; Otero, X. L.; Milori, D. M. B. P.; Haenel Gomes, F. (2008). "13C NMR and FTIR spectroscopy characterization of humic acids in spodosols under tropical rain forest in southeastern Brazil". Geoderma. 146 (3–4): 425–433. Bibcode:2008Geode.146..425G. doi:10.1016/j.geoderma.2008.06.018.
Knicker, H.; Almendros, G.; González-Vila, F. J.; Lüdemann, H. D.; Martin, F. (1995). "13C and 15N NMR analysis of some fungal melanins in comparison with soil organic matter". Organic Geochemistry. 23 (11–12): 1023–1028. Bibcode:1995OrGeo..23.1023K. doi:10.1016/0146-6380(95)00094-1.
"Vermiculture/Vermicompost". Agri.And.Nic.in. Port Blair: Department of Agriculture, Andaman & Nicobar Administration. 18 June 2011. Archived from the original on 17 January 2016. Retrieved 17 April 2009.