Question: Are both W. B. Yeats and Anita Loos a writer?

Context articles: W. B. Yeats
Hold Your Man
R. Beers Loos
Riffraff (1936 film)
Mary Loos
John Emerson (filmmaker)
Gentlemen Prefer Blondes (novel)
Anita Loos
Gentlemen Prefer Blondes (musical)
Gentlemen Marry Brunettes

William Butler Yeats ( ; 13 June 186528 January 1939) was an Irish poet and one of the foremost figures of 20th century literature.
 A pillar of both the Irish and British literary establishments, he helped to found the Abbey Theatre, and in his later years served as an Irish Senator for two terms.
 Yeats was a driving force behind the Irish Literary Revival along with Lady Gregory, Edward Martyn and others.
Hold Your Man is a 1933 American pre-Code romantic drama film directed by an uncredited Sam Wood and starring Jean Harlow and Clark Gable, the third of their six films together.
 The screenplay by Anita Loos and Howard Emmett Rogers was based on a story by Loos.
Richard Beers Loos (October 4, 1860 – March 6, 1944), was an American journalist and newspaper publisher.
 Loos was the father of Anita Loos, a famous American playwright and author who wrote, among other titles, "Gentlemen Prefer Blondes".
 Loos most often used the shortened form of his name for official work: R. Beers Loos.
 Anita Loos was born to Richard Beers Loos and Minnie Ellen Smith while the family lived near Sisson, California (today Mount Shasta).
 At that time, Loos owned a local newspaper called the "Sisson Mascot".
Riffraff is a 1936 American film starring Jean Harlow and Spencer Tracy.
 The movie was written by Frances Marion, Anita Loos, and H. W. Hannaford, and directed by J. Walter Ruben.
Mary Loos (May 6, 1910 – October 11, 2004) was an American actress, screenwriter and novelist.
 She was occasionally credited under her full name, Mary Anita Loos.
John Emerson (born Clifton Paden on May 29, 1874 – March 7, 1956) was an American stage actor, playwright, producer, and director of silent films (many featuring Douglas Fairbanks).
 Emerson was married to Anita Loos from June 15, 1919 until his death; prior to that they had functioned as a writing team for motion pictures and would continue to be credited jointly, even as Loos pursued independent projects.
Gentlemen Prefer Blondes: The Intimate Diary of a Professional Lady is a comic novel written by Anita Loos, first published in 1925.
 It is one of several famous novels published that year to chronicle the so-called Jazz Age, including Fitzgerald's "The Great Gatsby" and Van Vechten's "Firecrackers".
 Loos was inspired to write the book after watching a sexy blonde turn intellectual H. L. Mencken into a lovestruck schoolboy.
 Mencken, a close friend, actually enjoyed the work and saw to it that it was published.
 Originally published as a magazine series in "Harper's Bazaar", it was published as a book by Boni & Liveright in 1925 and became a runaway best seller, becoming the second best selling title of 1926 and earning the praise of no less than Edith Wharton who dubbed it "The Great American Novel."
Anita Loos (April 26, 1889 – August 18, 1981) was an American screenwriter, playwright and author, best known for her blockbuster comic novel, "Gentlemen Prefer Blondes".
 She wrote film scripts from 1912, and became arguably the first-ever staff scriptwriter, when D.W. Griffith put her on the payroll at Triangle Film Corporation.
 She went on to write many of the Douglas Fairbanks films, as well as the stage adaptation of Colette’s "Gigi".
Gentlemen Prefer Blondes is a musical with a book by Joseph Fields and Anita Loos, lyrics by Leo Robin, and music by Jule Styne, based on the best-selling novel of the same name by Loos.
 The story involves an American woman's voyage to Paris to perform in a nightclub.
Gentlemen Marry Brunettes is a 1955 technicolor romantic musical comedy film produced by Russ-Field productions, starring Jane Russell and Jeanne Crain, and released by United Artists.
 It was directed by Richard Sale, produced by the director and Bob Waterfield (Russell's husband) with Robert Bassler as executive producer, from a screenplay by Mary Loos and Sale, based on the novel "But Gentlemen Marry Brunettes" by Anita Loos.