APA Citation

Upgren, A. R. Many skies: Alternative histories of the sun, moon, planets, and stars.

Chicago Style Citation

Upgren, Arthur R.. Many Skies: Alternative Histories of the Sun, Moon, Planets, and Stars.

MLA Citation

Upgren, Arthur R.. Many Skies: Alternative Histories of the Sun, Moon, Planets, and Stars.

Warning: These citations may not always be 100% accurate.