Cita APA (7th ed.)

Wallingford, T. (2015). Switching to VOIP. SPD.

Cita Chicago (17th ed.)

Wallingford, Ted. Switching to VOIP. Mumbai: SPD, 2015.

Cita MLA (9th ed.)

Wallingford, Ted. Switching to VOIP. SPD, 2015.