"The Auld Triangle" is a song, which was first performed publicly as a part of the play "The Quare Fellow" (1954) by Brendan Behan.
 Brendan credited his friend Dicky Shannon as the writer.
 The song was later made famous by Luke Kelly, Ronnie Drew and The Dubliners in the late 1960s.
Borstal Boy is a play adapted by Frank McMahon from the 1958 autobiographical novel of Irish nationalist Brendan Behan of the same title.
 The play debuted in 1967 at the Abbey Theatre in Dublin, with Frank Grimes as the young Behan.
 McMahon won a New York Drama Critics' Circle Award in 1970 and Tony Award in 1970 for his adaptation.
Peadar Kearney (Irish: "Peadar Ó Cearnaígh" ] ; 12 December 1883 – 24 November 1942) was an Irish republican and composer of numerous rebel songs.
 In 1907 he wrote the lyrics to "The Soldier's Song" ("Amhrán na bhFiann"), now the Irish national anthem.
 He was the uncle of Irish writers Brendan Behan, Brian Behan, and Dominic Behan.
Karl Jay Shapiro (November 10, 1913 – May 14, 2000) was an American poet.
 He was appointed the fifth Poet Laureate Consultant in Poetry to the Library of Congress in 1946.
Borstal Boy is a 2000 British/Irish romantic drama film adaptation of the Brendan Behan autobiographical novel of the same name.
 The film is written and directed by Irish playwright Peter Sheridan.
Derry Power (born 1935) is an Irish actor born in Dublin.
 He appeared in the first production of Brendan Behan's The Quare Fellow at Dublin's Pike Theatre in 1954.
 He is best known for playing management genius Seamus Finnegan in the BBC Television sitcom "The Fall and Rise of Reginald Perrin", with the classic line "Would you be having a joke there with a simple, tongue-tied Irishman from the land of the bogs and the little people?"
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 In a long stage career he has featured in many plays in the Abbey Theatre; he has appeared in TV series from "Z-Cars" to "Ballykissangel" and in many films made in Ireland.
Borstal Boy is a 1958 autobiographical book by Brendan Behan.
 The story depicts a young, fervently idealistic Behan, who loses his naïveté over the three years of his sentence to a juvenile borstal, softening his radical Irish republican stance and warming to his British fellow prisoners.
 From a technical standpoint, the novel is chiefly notable for the art with which it captures the lively dialogue of the Borstal inmates, with all the variety of the British Isles' many subtly distinctive accents intact on the page.
 Ultimately, Behan demonstrated by his skillful dialogue that working class Irish Catholics and English Protestants actually had more in common with one another through class than they had supposed, and that alleged barriers of religion and ethnicity were merely superficial and imposed by a fearful middle class.
Paudge Rodger Behan ( ; born January 1965) is an Irish actor and writer.
 The son of IRA Chief of Staff Cathal Goulding and Beatrice ffrench-Salkeld, the widow of playwright Brendan Behan, Paudge Behan worked briefly as a journalist for a Dublin newspaper before turning to acting.
 After a series of minor film and television roles in the 1990s, he was handpicked by English novelist Barbara Taylor Bradford to appear as the male lead in a 1999 dramatisation of her book "A Secret Affair" (1996).
Brendan Francis Aidan Behan (christened Francis Behan) ( ; Irish: "Breandán Ó Beacháin" ; 9 February 1923 – 20 March 1964) was an Irish Republican, poet, short story writer, novelist, and playwright who wrote in both English and Irish.
 He is widely regarded as one of the greatest Irish writers and poets of all time.
Comhar (meaning "partnership") is a prominent literary journal in the Irish language, published by the company Comhar Teoranta.
 It was founded in 1942, and has published work by some of the most notable writers in Irish, including Máirtín Ó Cadhain, Seán Ó Ríordáin, Máirtín Ó Direáin, Máire Mhac an tSaoi and Brendan Behan.
 Comhar also publishes books in Irish (around three a year).

Question: What profession did Karl Shapiro and Brendan Behan have in common?
Answer: Poet