Namgyal, T. and Kongmanus, K. 2018. Effectiveness of a Mathematics Instructional Package on Pólya’s Steps Including Video Clips to Enhance Problem Solving Abilities of 6th Grade Students in Bhutan. International Journal of Engineering & Technology. 7, 4.38 (Dec. 2018), 965–969. DOI:https://doi.org/10.14419/ijet.v7i4.38.27618.