Citazione Stile APA (7a Edizione)

Johnson, R. M. (1995). Picture communication symbols (Wordless ed.). Mayer-Johnson.

Citazione stile Chigago Style (17a edizione)

Johnson, Roxanna Mayer. Picture Communication Symbols. Wordless ed. Solana Beach, Calif: Mayer-Johnson, 1995.

Citatione MLA (9a ed.)

Johnson, Roxanna Mayer. Picture Communication Symbols. Wordless ed. Mayer-Johnson, 1995.