SengkeyD.F., PaturusiS.D.E. and SambulA.M. 2019. Identifying Students’ Pre-Classroom Behaviors in a Flipped Learning Environment. Journal of Sustainable Engineering: Proceedings Series. 1, 2 (Sep. 2019), 143-149. DOI:https://doi.org/10.35793/joseps.v1i2.19.