Cita APA (7th ed.)

O'Neil, J. J., & Oyer, H. J. (1961). Visual communication for the hard of hearing; history, research, mehtods. Prentice - Hall.

Cita Chicago (17th ed.)

O'Neil, John Joseph, i Herbert J. Oyer. Visual Communication for the Hard of Hearing; History, Research, Mehtods. Englewood Cliff, N.J: Prentice - Hall, 1961.

Cita MLA (9th ed.)

O'Neil, John Joseph, i Herbert J. Oyer. Visual Communication for the Hard of Hearing; History, Research, Mehtods. Prentice - Hall, 1961.