http://repository.uhamka.ac.id/id/eprint/12307/
Polya’s Four Phases Exploration in Solving Linear Program Story
Questions Based on Student Beliefs
Soebagyo, Joko
http://repository.uhamka.ac.id/id/eprint/12307/1/Polya%E2%80%99s%20Four%20Phases%20Exploration%20in%20Solving%20Linear%20Program%20Story%20Questions%20Based%20on%20Student%20Beliefs.pdf