Adams, B. (1991). Facing the Romantic Void: Caspar David Friedrich. Art in America.
Cita Chicago (17th ed.)Adams, Brooks. "Facing the Romantic Void: Caspar David Friedrich." Art in America 1991.
Cita MLA (8th ed.)Adams, Brooks. "Facing the Romantic Void: Caspar David Friedrich." Art in America, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.