Ratnawati, W., Sutama, and Sabar Narimo. “Development of Mathematics Teaching Materials to Improve Higher Order Thinking Skills in Grade 3rd Students in Elementary School”. JTP - Jurnal Teknologi Pendidikan, Vol. 24, no. 2, Aug. 2022, pp. 236-45, doi:10.21009/jtp.v24i2.28318.