What was the nationality of the novelist whose eighteenth novel was published in 1976?
Iris Murdoch Dame Jean Iris Murdoch ( ; 15 July 1919 – 8 February 1999) was an Anglo-Irish novelist and philosopher, best known for her novels about good and evil, sexual relationships, morality, and the power of the unconscious. Her first published novel, "Under the Net", was selected in 1998 as one of Modern Library's 100 best English-language novels of the 20th century. In 1987, she was made a Dame Commander of the Order of the British Empire. Her books include "The Bell" (1958), "A Severed Head" (1961), "The Red and the Green" (1965), "The Nice and the Good" (1968), "The Black Prince" (1973), "Henry and Cato" (1976), "The Sea, the Sea" (1978, Booker Prize), "The Philosopher's Pupil" (1983), "The Good Apprentice" (1985), "The Book and the Brotherhood" (1987), "The Message to the Planet" (1989), and "The Green Knight" (1993). In 2008, "The Times" ranked Murdoch twelfth on a list of "The 50 greatest British writers since 1945".
Barbara Cartland Dame Mary Barbara Hamilton Cartland DBE CStJ (9 July 1901 – 21 May 2000) was an English author of romance novels, one of the best-selling authors as well as one of the most prolific and commercially successful worldwide of the twentieth century. Her 723 novels were translated into 38 languages and she continues to be referenced in the "Guinness World Records" for the most novels published in a single year in 1976. As Barbara Cartland she is known for her numerous romantic novels but she also wrote under her married name of Barbara McCorquodale and briefly under the pseudonym of Marcus Belfry. She wrote more than 700 books, as well as plays, music, verse, drama, magazine articles and operetta, and was a prominent philanthropist. She reportedly sold more than 750 million copies. Other sources estimate her book sales at more than two billion copies. She specialised in 19th-century Victorian era pure romance. Her novels all featured portrait-style artwork, particularly the cover art, usually designed by Frances Marshall.