1. Virginia Murray Sowell Center for Research and Education in Visual Impairment, Texas Tech University, Box 41071, Lubbock, TX 79404-1071
2. Virginia Murray Sowell Center for Research and Education in Visual Impairment, Texas Tech University
3. Department of Education, University of Alabama in Huntsville, 301 Sparkman Drive, 247 B Morton Hall, Huntsville, AL 35899
4. Department of Educational Psychology, College of Education, Texas Tech University, Box 41071, Lubbock, TX 79404-1071