एपीए उद्धरण

(1962). Penrose annual: Review of the graphic arts. London: Lund Humphries & co., Ltd.

शिकागो स्टाइल उद्धरण

Penrose Annual: Review of the Graphic Arts. London: Lund Humphries & co., Ltd, 1962.

एमएलए उद्धरण

Penrose Annual: Review of the Graphic Arts. London: Lund Humphries & co., Ltd, 1962.