C. M. Estepp, C. T. Stripling, N. W. Conner, A. Giorgi, and T. G. Roberts, “An Examination of the Learning Activities, Cognitive Level of Instruction, and Teacher Immediacy Behaviors of Successful Instructors in a College of Agriculture”, JAE, vol. 54, no. 2, pp. 15–28, Jun. 2013.