Jersky, Bryan. "L4: Soil and Compost". OER Commons. Institute for the Study of Knowledge Management in Education, 05 May 2015. Web. 31 Aug. 2024. <https://oercommons.org/authoring/8322-l4-soil-and-compost>.
Jersky, B. (2015, May 05). L4: Soil and Compost. OER Commons. Retrieved August 31, 2024, from https://oercommons.org/authoring/8322-l4-soil-and-compost.