Fraknoi, Andrew. "Introduction to the Solar System - Sample Syllabus". OER Commons. Institute for the Study of Knowledge Management in Education, 06 Jan. 2017. Web. 24 Jan. 2020. <https://www.oercommons.org/authoring/19408-introduction-to-the-solar-system-sample-syllabus>.
Fraknoi, A. (2017, January 06). Introduction to the Solar System - Sample Syllabus. OER Commons. Retrieved January 24, 2020, from https://www.oercommons.org/authoring/19408-introduction-to-the-solar-system-sample-syllabus.