Dongwi, Beata Lididimikeni. 2018. “Using the Van Hiele Phases of Instruction to Design and Implement a Circle Geometry Teaching Programme in a Secondary School in Oshikoto Region: A Namibian Case Study”. The Namibia CPD Journal for Educators, February, 4-62. https://doi.org/10.32642/ncpdje.vi.1270.