Question: Are Richard Aldington and Thomas B. Costain both writers?

Context articles: The Silver Chalice
The Silver Chalice (film)
H.D.
Life for Life's Sake
Richard Aldington
Molly Costain Haycraft
The Black Rose (novel)
Thomas B. Costain
Thomas B. Finley House
The Black Rose

The Silver Chalice is a 1952 English language historical novel by Thomas B. Costain.
 It is the fictional story of the making of a silver chalice to hold the Holy Grail (itself here conflated with the Holy Chalice) and includes 1st century biblical and historical figures: Luke, Joseph of Arimathea, Simon Magus and his companion Helena, and the apostle Peter.
The Silver Chalice is a 1954 American historical epic film directed and producer by Victor Saville, based on Thomas B. Costain's 1952 novel of the same name.
 It was Saville's last film and marked the acting debut of Paul Newman; despite being nominated for a Golden Globe Award for his performance, Newman later called it "the worst motion picture produced during the 1950s".
Hilda "H.D." Doolittle (September 10, 1886 – September 27, 1961) was an American poet, novelist, and memoirist known for her association with the early 20th century avant-garde Imagist group of poets such as Ezra Pound and Richard Aldington.
 She published under the pen name of H.D.
Life For Life's Sake: A Book of Reminiscences is a book of memoirs written by Richard Aldington and published by the Viking Press in 1941.
 Chapter IX deals with the early history of Imagism.
Richard Aldington (8 July 1892 – 27 July 1962), born Edward Godfree Aldington, was an English writer and poet.
Molly Costain Haycraft (6 December 1911 – 5 June 2005) was a Canadian author.
 She was born in Toronto, Canada, and spent her childhood in Philadelphia, where her father, the well-known novelist Thomas B. Costain, was an editor for "The Saturday Evening Post".
 She was the author of several novels about women in English royal history.
 These include "The Lady Royal," "The Reluctant Queen," and "Too Near the Throne."
 She died in Hightstown, NJ, in 2005
The Black Rose is a 1945 historical novel by Thomas B. Costain.
 It is a fictional story set in the 13th century about a young Saxon who journeys to the far-away land of Cathay in search of fortune.
 Included in this narrative are several notable figures: Roger Bacon, Bayan Hundred Eyes, Edward I of England and his consort Eleanor of Castile.
 Costain also includes a passage depicting the building of a "galere da mercato" at the Venetian Arsenal in a single day.
Thomas Bertram Costain (May 8, 1885 – October 8, 1965) was a Canadian journalist who became a best-selling author of historical novels at the age of 57.
The Thomas B. Finley House, also known as The Oaks, is a historic home located at North Wilkesboro, Wilkes County, North Carolina.
 It was designed by noted architect Norma Bonniwell (1877–1961) and built in 1893.
 It is a two-story, Queen Anne style frame dwelling with a one-story rear ell.
 It features a hip and gable roof, corner tower, fish-scale-cut wood shingles, and one-story, hip-roofed, wraparound porch.
 It was built for prominent attorney Thomas B. Finley (1862–1942), whose firm Finley and Hendren occupied the Thomas B. Finley Law Office at Wilkesboro.
The Black Rose is a 1950 20th Century Fox Technicolor film starring Tyrone Power and Orson Welles, loosely based on Thomas B. Costain's book.
 It was filmed partly on location in England and Morocco which substitutes for the Gobi Desert of China.
 The film was partly conceived as a follow-up to the movie "Prince of Foxes", and reunited the earlier film's two stars.