Repi, Elra, 		Suriani, Ni, AND 		Waworuntu, Freetje.
" The Effect of Learning Cycle 7E Model on Buffer Solution Subject on Learning Outcomes of Class XI Students of SMA N 2 Langowan" <em>Oxygenius: Journal Of Chemistry Education</em> [Online], Volume 1 Number 2 (31 December 2019)