1. Alpert, C. L., Keefer, M. A. &Fisher, R. (1992, October). Combined code: Milieu, responsiveinteractive and hybrid language teaching. Peabody College of Vanderbilt University, Nashville, TN.
2. DUM, L. M. & Dunn, L. M. (1981). Peabody Picture Vocabulary Test- Revised. Circle Pines, MN: American Guidance Service.
3. AN ANALYSIS OF MAINTENANCE FOLLOWING FUNCTIONAL COMMUNICATION TRAINING