GolinkoffR. M., & Hirsh-PasekK. (2000). Word learning: Icon, index, or symbol? Becoming a word learner: A debate on lexical acquisition.New York: Oxford University Press.
2.
JoffeeE., & RikhyeC. H. (1991). Orientation and mobility for students with severe visual and multiple impairments: A new perspective. Journal of Visual Impairment & Blindness, 85, 211–216.
3.
LancioniG. E., O'ReillyM. F., & OlivaD. (2002). Engagement in cooperative and individual tasks: Assessing the performance and preference of persons with multiple disabilities. Journal of Visual Impairment & Blindness, 96, 50–53.
4.
LundS. K., & TrohaJ. M. (2008). Teaching young people who are blind and have autism to make requests using a variation on the picture exchange communication system with tactile symbols: A preliminary investigation. Journal of Autism and Developmental Disorders, 38, 719–730.
5.
ParkK. (1997). How do objects become objects of reference: A review of the literature on objects of reference and a proposed model for the use of objects in communication. British Journal of Special Education, 24, 108–114.
6.
RowlandC., & SchweigertP. (1989). Tangible symbols: Symbolic communication for individuals with multisensory impairment. AAC Augmentative and Alternative Communication, 5, 226–234.
7.
RowlandC., & SchweigertP. (2000). Tangible symbols, tangible outcomes. AAC Augmentative and Alternative Communication, 16, 61–76.
8.
TriefE. (2007). The use of tangible cues for children with multiple disabilities and visual impairment. Journal of Visual Impairment & Blindness, 101, 613–619.
9.
VickerB. (1996). Using tangible symbols for communication purposes: An optional step in building two-way communication. (ERIC Document Reproduction Service No. ED 405712.)
10.
WernerH., & KaplanB. (1988). On developmental changes in the symbolic process. In FranklinM., & BartenS. (Eds.), Child language: A reader (pp. 7–9). New York: Oxford University Press.
11.
WestlingD. L., & FoxL. (2004). Teaching students with severe disabilities (3rd ed.). Upper Saddle River, NJ: Pearson/Merrill Prentice Hall.
