Question: Robert E. Howard and Andre Dubus III, are of which nationality?

Context paragraphs:
The Garden of Last Days: The Garden of Last Days is a 2008 novel by Andre Dubus III.  It tells the interweaving stories of several individuals in Florida in the days before the September 11 attacks.  The book is a follow up to "House of Sand and Fog".

Robert E. Howard: Robert Ervin Howard (January 22, 1906 – June 11, 1936) was an American author who wrote pulp fiction in a diverse range of genres.  He is well known for his character Conan the Barbarian and is regarded as the father of the sword and sorcery subgenre.

Killings (short story): Killings is a short tale written by Andre Dubus in 1979.  The short story entails how a man seeks revenge after the death of his son in cold blood.  In 2001, the story was adapted into Todd Field's film, "In the Bedroom".  The film starred Sissy Spacek, Tom Wilkinson, and Marisa Tomei, and was nominated for five Academy Awards – Best Picture, Actor in a Leading Role (Wilkinson), Actress in a Leading Role (Spacek), Actress in a Supporting Role (Tomei), and Best Writing, Screenplay Based on Material Previously Published (Robert Festinger & Field).  After the film's release the story was republished in a collection called "In the Bedroom" for which Field wrote the preface.

Delivering (film): Delivering is a 1993 short film that Todd Field, while a fellow at the AFI Conservatory, adapted from the story of the same name by Andre Dubus.  It is a dramatic piece that takes place on the day two brothers discover their mother has abandoned the family.  This film is notable as it was the first time Field adapted Dubus' work to film.  The next time would be for his Academy Award nominated feature debut, "In the Bedroom", which was based on Dubus' short story, "Killings".  Years after Field's graduation from the AFI, "Delivering" continued to be screened in the classroom.

In the Bedroom: In the Bedroom is a 2001 American crime drama film directed by Todd Field, and dedicated to Andre Dubus, whose short story "Killings" is the source material on which the screenplay, by Field and Robert Festinger, is based.  The film stars Tom Wilkinson, Sissy Spacek, Nick Stahl, Marisa Tomei, and William Mapother.

House of Sand and Fog (novel): House of Sand and Fog is a 1999 novel by Andre Dubus III.  It was selected for Oprah's Book Club in 2000, was a finalist for the National Book Award for Fiction, and was adapted into the 2003 film, "House of Sand and Fog".

DeLauné Michel: DeLauné Michel is an American author and actress.  She was raised in southern Louisiana in a literary family which includes her uncle, Andre Dubus; her mother, Elizabeth Nell Dubus; and her cousins, mystery writer James Lee Burke, Andre Dubus III ("House of Sand and Fog"), and Alafair Burke.

Townie: A Memoir: Townie – A Memoir is a 2011 memoir by American novelist and short story writer Andre Dubus III.  It details Dubus' childhood in Haverhill, Massachusetts and his frequently turbulent relationship with his father Andre Dubus II.

Andre Dubus III: Andre Dubus III (born September 11, 1959) is an American novelist and short story writer.  He is a member of the faculty at the University of Massachusetts Lowell.

House of Sand and Fog (film): House of Sand and Fog is a 2003 American drama film directed by Vadim Perelman.  The screenplay by Perelman and Shawn Lawrence Otto is based on the novel of the same name by Andre Dubus III.

Supporting paragraphs: Robert E. Howard Andre Dubus III
Answer: American