Dillon CL, Hengst HR, Zoller D. Instructional Strategies and Student Involvement in Distance Education: A Study of the Oklahoma Televised Instruction System. IJEDE [Internet]. 1991 Apr. 3 [cited 2024 May 13];6(1):28-41. Available from: https://www.ijede.ca/index.php/jde/article/view/392