Wäspe, R. (1989). Richard Long: Angel flying too close to the ground. Druckerei Künzler.
Cita Chicago (17th ed.)Wäspe, Roland. Richard Long: Angel Flying Too Close to the Ground. St. Gallen: Druckerei Künzler, 1989.
Cita MLA (8th ed.)Wäspe, Roland. Richard Long: Angel Flying Too Close to the Ground. Druckerei Künzler, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.