Question: The Celestial Plot is a book by which the fiction writer of what nationality?

Context paragraphs:
Sonia Greene: Sonia Haft Greene Lovecraft Davis (16 March 1883 - 26 December 1972) was a one-time pulp fiction writer and amateur publisher, a single mother, business woman and successful milliner who bankrolled several fanzines in the early twentieth century.  She is best known for her two-year marriage to American weird fiction writer H. P. Lovecraft.  She was a president of the United Amateur Press Association.

The Celestial Plot: The Celestial Plot (Spanish: "La trama celeste" ) is a book by Adolfo Bioy Casares.  It is a collection of short stories and includes a work with the same name.

Octavia E. Butler: Octavia Estelle Butler (June 22, 1947February 24, 2006) was an American science fiction writer.  A multiple recipient of both the Hugo and Nebula awards, in 1995 she became the first science fiction writer to receive the MacArthur Fellowship.

Adolfo Bioy Casares: Adolfo Bioy Casares (] ; September 15, 1914 – March 8, 1999) was an Argentine fiction writer, journalist, and translator.  He was a friend and frequent collaborator with his fellow countryman Jorge Luis Borges, and is the author of the fantastic fiction novel "The Invention of Morel".

Taku Mayumura: Taku Mayumura (眉村 卓 "Mayumura Taku", 20 October 1934 - ) is a Japanese science fiction writer who won the Seiun Award for Novel twice.  In 2004 his Shiseikan (司政官, one story of the Shiseikan series), written in 1974, was translated into English. .  Mayumura is also a young adult fiction writer whose works have been adapted into TV drama, film, and anime.

Arrowhead (science fiction venue): Arrowhead is the name that science fiction writer James Blish and his wife, literary agent and science fiction writer Virginia Kidd, gave to their home in Milford, Pennsylvania.  The Virginia Kidd Literary Agency has been operating continuously at Arrowhead since 1965.

Donald Wandrei: Donald Albert Wandrei (April 20, 1908 – October 15, 1987) was an American science fiction, fantasy and weird fiction writer, poet and editor.  He was the older brother of science fiction writer and artist Howard Wandrei.  He had fourteen stories in "Weird Tales", another sixteen in "Astounding Stories", plus a few in other magazines including "Esquire".  He was the co-founder (with August Derleth) of the prestigious fantasy/horror publishing house Arkham House.

Megan Staffel: Megan Staffel (born 1952, Philadelphia, Pennsylvania, USA) is an American fiction writer and essayist.  She is the author of two novels, "The Notebook of Lost Things" and "She Wanted Something Else", and three story collections, "A Length of Wire and Other Stories", "Lessons In Another Language" and "The Exit Coach".  Her story collection, "Lessons in Another Language," was awarded the 2011 IPPY AWARD for Bronze Medal Winner in the Short Story and the 2011 Foreword Review's "Book of the Year Award" for Silver Medal Winner in the Short Story.  Her stories have appeared in numerous journals, including Ploughshares and New England Review.  Her essays on the craft of fiction appear in "A Kite in the Wind," edited by Andrea Barrett and Peter Turchi, and "Letters to a Fiction Writer," edited by Frederick Busch.  She teaches in the MFA Program for Writers at Warren Wilson College.

Brian Plante: Brian Plante (born 1956) is an American science fiction writer.  As of 2007, he had published 49 short stories.  "Analog" magazine has published 16 of his stories and most of the recent ones.  Plante has written several sarcastic essays on writing, including the "Chronicles of the Garden Valley Writers," an account of dynamics in a fiction writer criticism group.  His non-fiction has appeared in "Manifest Destiny", "Fantastic Collectibles", and from 1995 to 1998 as a monthly column in "The New Jersey Graveline".

Jim Aikin: James Douglas Aikin (born 1948) is an American science fiction writer based in Livermore, California.  He is also a music technology writer, an interactive fiction writer, freelance editor and writer, cellist, and teacher.  He frequently writes articles for various music industry magazines, including "Electronic Musician", "Keyboard Magazine", and "Mix".

Supporting paragraphs: The Celestial Plot Adolfo Bioy Casares
Answer: Argentine