du Preez, C. 2003. Sustainable land use and soil quality: organic matter as an indicator. Suid-Afrikaans Tydskrif vir Natuurwetenskap en Tegnologie / <i>South African Journal of Science and Technology</i&gt;. 22, 4 (Sep. 2003), 106-112. DOI:https://doi.org/10.4102/satnt.v22i4.219.