Cita APA (7th ed.)

Guthke, K. S. Are we alone?: The idea of extraterrestrial intelligence in philosophy and literature from Copernicus to H.G. Wells / Karl S. Guthke. Utopian vision, technological innovation and poetic imagination.(1990).

Cita Chicago (17th ed.)

Guthke, Karl S. "Are We Alone?: The Idea of Extraterrestrial Intelligence in Philosophy and Literature from Copernicus to H.G. Wells / Karl S. Guthke." Utopian Vision, Technological Innovation and Poetic Imagination.(1990) .

Cita MLA (8th ed.)

Guthke, Karl S. "Are We Alone?: The Idea of Extraterrestrial Intelligence in Philosophy and Literature from Copernicus to H.G. Wells / Karl S. Guthke." Utopian Vision, Technological Innovation and Poetic Imagination.(1990), .

Atenció: Aquestes cites poden no estar 100% correctes.