Ultimatum: Classic Book Guide and Free Edition
Ultimatum: author and translator credits, catalogue synopsis, subjects and links to the Gutenberg reading formats.

Ultimatum is catalogued by Project Gutenberg with author credits for Aycock, Roger D. (1914–2004).
Catalogue synopsis
Project Gutenberg supplies this automated synopsis of the opening text:
"Ultimatum" by Roger D. Aycock is a science fiction novel written in the early 1950s. The story revolves around an encounter between an Earthman, Winant, and an alleged Martian envoy named Yardana, who comes to warn humanity about the dangers of their technological advancements and the influence of alien entities on Earth. The narrative unfolds in a tense atmosphere where the stakes involve the fate of multiple worlds due to human warfare and scientific progress. The plot is set in a small Indiana hotel room, where Winant encounters his uncle, who claims to be from Mars. As the story progresses, Yardana reveals that Martians have been observing Earth and perceive humanity's atomic discoveries as a significant threat, potentially endangering their civilization. Winant, initially skeptical, learns that Yardana is on a mission to advocate for Earth's destruction to safeguard the Martian way of life. However, the story takes an unexpected twist as Winant reveals his own intentions, equipped with a weapon from Venus, leading to a dramatic and shocking conclusion that questions the motivations and survival instincts of different civilizations.
Book and edition facts
- Title: Ultimatum
- Author credits: Aycock, Roger D. (1914–2004)
- Catalogue language: English
Catalogue subjects
- Earth (Planet) -- Fiction
- Human-alien encounters -- Fiction
- Science fiction
- Short stories
Gutenberg collections
- Category: Novels
- Category: Science-Fiction & Fantasy
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View the complete Gutenberg catalogue record. Project Gutenberg identifies this edition as public domain in the United States; that designation does not establish its copyright status in every country.
Source notes
Catalogue metadata is public domain and is supplied through Gutendex, which imports Gutenberg's machine-readable catalogue. The automated synopsis is source-supplied, not an independently verified review. Author dates above describe the credited people; no ebook release date is presented as the book's original publication date.


