Yunita, Zaini, M. and Kaspul 2022. Quality of Electronic Student Worksheets on The Concept Ferns (Pteridophyte) to Improve High School Level Critical Thinking Skills. Islamic Journal of Integrated Science Education (IJISE). 1, 2 (Jul. 2022), 94–102. DOI:https://doi.org/10.30762/ijise.v1i2.284.