APA

Murray، w, Wingfield، J.H, .The Holiday Camp Mystery. London: Ladybird.

Chicago

Murray، w, Wingfield، J.H, .The Holiday Camp Mystery. London: Ladybird.

Harvard

Murray، w, Wingfield، J.H, .The Holiday Camp Mystery. London: Ladybird.

MLA

Murray، w, Wingfield، J.H, .London: Ladybird. .