Title: Memory, Sorrow, and Thorn
Content:  American author George R. R. Martin was a fan of Memory, Sorrow, and Thorn. Martin has cited Williams' work as a key influence of his own epic high fantasy novel series, A Song of Ice and Fire. American author Christopher Paolini, writer of The Inheritance Cycle, also cited Memory, Sorrow and Thorn as an influence, calling it "one of the great fantasy epics of all time."
Title: Memory, Sorrow, and Thorn
Content:  Memory, Sorrow, and Thorn is a trilogy of epic fantasy novels by American writer Tad Williams, comprising The Dragonbone Chair (1988), Stone of Farewell (1990), and To Green Angel Tower (1993). Memory, Sorrow, and Thorn takes place on the fictional continent of Osten Ard, comprising several united countries. Williams used several characters, both protagonist and antagonist, as point of view characters throughout the novels, presenting the reader with an assortment of disparate and subjective viewpoints. A novelette set in the world of Osten Ard, The Burning Man, was released in 1998 and later published as a graphic novel. A sequel trilogy, The Last King of Osten Ard, began publication in 2017, following 2017's The Heart of What Was Lost. A prequel to the entirety of Osten Ard, Brothers of the Wind, is also expected to be published.
Title: Memory, Sorrow, and Thorn
Content:  A nationwide bestseller in the United States, Memory, Sorrow, and Thorn was well received by book critics. Of Stone of Farewell, Locus called it "an epic fantasy you can get lost in for days, not just hours". Publishers Weekly said that Stone of Farewell is a "panoramic, vigorous, often moving sequel to The Dragonbone Chair". Of the series, Amaranth Magazine said, "This is quite simply the best story I have read next to LORD OF THE RINGS…destined to become among the greatest Fantasy epics of all time." The series was recommended in the New York Times podcast The Argument on April 4, 2019.
Title: Memory, Sorrow, and Thorn
Content:  Memory, Sorrow, and Thorn takes place on the fictional continent of Osten Ard, home to several united races, including humans, elf-like immortals known as Sithi, and dwarf-like mountain-dwellers named Qanuc. Most of these races have been living in relative unity for decades, thanks to King John the Presbyter (also known as Prester John), who is known to have slain a dragon. The first novel opens when Prester John's health in his advanced age is failing and his sons, Elias and Josua, quarrel over who will ascend to the throne. Meanwhile, a dark secret held by Prester John, and the ambitions of a priest named Pryrates, threaten the stability of the continent. Williams 
Title: Memory, Sorrow, and Thorn
Content:  To Green Angel Tower's paperback edition is presented in two parts due to its sheer size, totaling nearly 1600 pages in length. Parts 1 and 2 were subtitled Siege and Storm, respectively, in their United Kingdom pressings.
Title: The Memory Game
Content:  The Memory Game is a psychological thriller by London journalists, Nicci Gerrard and Sean French, under the pseudonym Nicci French. It was their first novel (followed by The Safe House) and originally published by William Heinemann in 1997.
Title: The Heart of What Was Lost
Content:  Jason Heller, a book reviewer for NPR, reviewed the book, stating the novel balances "warmth with grimness, and gentle bits of humor with violence and vengeance. Williams has tapped back into the dynamic that made "Memory, Sorrow, and Thorn" so absorbing." Aidan Moher at Barnes & Noble's fantasy blog called The Heart of What Was Lost "a glorious return to a landmark work of Epic Fantasy".
Title: Memory (novel)
Content:  Memory is a science fiction novel by American writer Lois McMaster Bujold, first published in October 1996. It is a part of the Vorkosigan Saga, and is the eleventh full-length novel in publication order.
Title: Memory (H. P. Lovecraft)
Content:  "Memory" is a flash fiction short story by American horror and science fiction writer H. P. Lovecraft, written in 1919 and published in May 1923 in The National Amateur.
Title: The Book of Sorrows
Content:  The Book of Sorrows is the sequel novel to Walter Wangerin, Jr.'s The Book of the Dun Cow. Published by Zondervan in 1985, it was received quite well by publications such as the Washington Post, whose review called it "a beautifully written fantasy anchored starkly in reality." Readers noted it for its melancholy tone, with one of the main themes of the book being sorrow.

Question: Who is the author of Memory, Sorrow, and Thorn?
Answer: Tad Williams.