Darmawan, R., & Susetyo, B. (2025). IMPROVING THE QUALITY OF WORK ON CULVERT UNDERPASS BOX STRUCTURES USING THE LEAN SIX SIGMA METHOD. Jurnal Pensil : Pendidikan Teknik Sipil, 14(1), 1–19. https://doi.org/10.21009/jpensil.v14i1.45230