Barnes, Timothy. "Catapult Challenge". OER Commons. Institute for the Study of Knowledge Management in Education, 05 Dec. 2018. Web. 31 Mar. 2023. <https://www.oercommons.org/authoring/50528-catapult-challenge>.
Barnes, T. (2018, December 05). Catapult Challenge. OER Commons. Retrieved March 31, 2023, from https://www.oercommons.org/authoring/50528-catapult-challenge.