Hughes, R., & Olsen, J. (1965). Donald Friend: By Robert Hughes. With a foreword by John Olsen. Edwards & Shaw.
Lua i Stíl Chicago (17ú heag.)Hughes, Robert, agus John Olsen. Donald Friend: By Robert Hughes. With a Foreword by John Olsen. Sydney: Edwards & Shaw, 1965.
Lua MLA (8ú heag.)Hughes, Robert, agus John Olsen. Donald Friend: By Robert Hughes. With a Foreword by John Olsen. Edwards & Shaw, 1965.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.