Cita APA

O'Cathain, A., Munro, J. F., Nicholl, J. P., & Knowles, E. (2000). How helpful is NHS Direct? Postal survey of callers. British Medical Journal.

Citación estilo Chicago

O'Cathain, A., J F. Munro, J P. Nicholl, y E. Knowles. How Helpful Is NHS Direct? Postal Survey of Callers. British Medical Journal, 2000.

Cita MLA

O'Cathain, A., J F. Munro, J P. Nicholl, y E. Knowles. How Helpful Is NHS Direct? Postal Survey of Callers. British Medical Journal, 2000.