Question: Which Hugo Award winning science fiction novel was the musical Charlie and Algernon based on?

Context articles: John W. Campbell Award for Best New Writer
Hugo Award for Best Fan Artist
A Deepness in the Sky
John Scalzi
Hugo Award for Best Related Work
The Windup Girl
Flowers for Algernon
Charlie and Algernon
Hugo Award for Best Graphic Story
Blindsight (Watts novel)

The John W. Campbell Award for Best New Writer is an American award given annually to the best new writer whose first professional work of science fiction or fantasy was published within the two previous calendar years.
 The prize is named in honor of science fiction editor and writer John W. Campbell, whose science fiction writing and role as editor of "Analog Science Fiction and Fact" made him one of the most influential editors in the early history of science fiction.
 The award is sponsored by Dell Magazines, which publishes "Analog".
 The nomination and selection process is administered by the World Science Fiction Society (WSFS) represented by the current Worldcon committee, and the award is presented at the Hugo Award ceremony at the Worldcon, although it is not itself a Hugo Award.
 All nominees receive a pin, while the winner receives a plaque.
 Beginning in 2005, the award has also included a tiara; created at the behest of 2004 winner Jay Lake and 2005 winner Elizabeth Bear, the tiara is passed from each year's winner to the next.
The Hugo Awards are presented every year by the World Science Fiction Society for the best science fiction or fantasy works and achievements of the previous year.
 The award is named after Hugo Gernsback, the founder of the pioneering science fiction magazine "Amazing Stories", and was once officially known as the Science Fiction Achievement Award.
 The award has been described as "a fine showcase for speculative fiction" and "the best known literary award for science fiction writing".
 The Hugo Award for Best Fan Artist is given each year for artists of works related to science fiction or fantasy which appeared in low- or non-paying publications such as semiprozines or fanzines.
 A Hugo Award for professional artists is also given.
 The fan award was first presented in 1967 and has been awarded annually.
 Beginning in 1996, Retrospective Hugo Awards, or "Retro Hugos", have been available to be awarded for years 50, 75, or 100 years prior in which no awards were given.
 To date, Retro Hugo awards have been awarded for 1939, 1941, 1946, 1951, and 1954, although the 1939, 1941, and 1954 Retro Hugos received insufficient nominations for the Fan Artist Hugo to make the ballot.
A Deepness in the Sky is a Hugo Award–winning science fiction novel by Vernor Vinge.
 Published in 1999, the novel is a loose prequel (set twenty thousand years earlier) to his earlier novel "A Fire Upon the Deep" (1992).
 The title is coined by one of the story's main characters in a debate, in a reference to the hibernating habits of his species and to the vastness of space.
John Michael Scalzi II (born May 10, 1969) is an American science fiction author and former president of the Science Fiction and Fantasy Writers of America.
 He is best known for his "Old Man's War" series, three novels of which have been nominated for the Hugo Award, and for his blog "Whatever", where he has written on a number of topics since 1998.
 He won the Hugo Award for Best Fan Writer in 2008 based predominantly on that blog, which he has also used for several charity drives.
 His novel "Redshirts" won the 2013 Hugo Award for Best Novel.
 He has written non-fiction books and columns on diverse topics such as finance, video games, films, astronomy, writing and politics, and served as a creative consultant for the TV series "Stargate Universe".
The Hugo Awards are given every year by the World Science Fiction Society for the best science fiction or fantasy works and achievements of the previous year.
 The award is named after Hugo Gernsback, the founder of the pioneering science fiction magazine "Amazing Stories", and was once officially known as the Science Fiction Achievement Award.
 The award has been described as "a fine showcase for speculative fiction" and "the best known literary award for science fiction writing".
 The Hugo Award for Best Related Work is given each year for primarily non-fiction works related to science fiction or fantasy, published in English or translated into English during the previous calendar year.
 Awards are also given out for works of fiction in the novel, novella, novelette, and short story categories.
The Windup Girl is a biopunk science fiction novel by American writer Paolo Bacigalupi.
 It was his debut novel and was published by Night Shade Books on September 1, 2009.
 The novel was named as the ninth best fiction book of 2009 by "TIME" magazine, and as the best science fiction book of the year in the Reference and User Services Association's 2010 Reading List.
 The work won the 2010 Nebula Award and the 2010 Hugo Award (tied with "The City & the City" by China Miéville for the Hugo Award), both for best novel.
 This book also won the 2010 Compton Crook Award and the 2010 Locus Award for best first novel.
Flowers for Algernon is a science fiction short story and subsequent novel written by Daniel Keyes.
 The short story, written in 1958 and first published in the April 1959 issue of "The Magazine of Fantasy & Science Fiction", won the Hugo Award for Best Short Story in 1960.
 The novel was published in 1966 and was joint winner of that year's Nebula Award for Best Novel (with "Babel-17").
Charlie and Algernon is a musical with a book and lyrics by David Rogers and music by Charles Strouse.
 It is based on the novel "Flowers for Algernon" by Daniel Keyes.
 It received its premiere on 21 December 1978 at The Citadel Theater, in Edmonton, Canada.
The Hugo Awards are given every year by the World Science Fiction Society for the best science fiction or fantasy works and achievements of the previous year.
 The award is named after Hugo Gernsback, the founder of the pioneering science fiction magazine "Amazing Stories", and was once officially known as the Science Fiction Achievement Award.
 It has been described as "a fine showcase for speculative fiction" and "the best known literary award for science fiction writing".
 The Hugo Award for Best Graphic Story is given each year for science fiction or fantasy stories told in graphic form and published in English or translated into English during the previous calendar year.
 The Hugo Award for Best Graphic Story has been awarded annually since 2009.
 It was started then with the requirement that it would only continue as an official award if approved again by the World Science Fiction Society after that year.
 It was, and was again awarded in 2010; it was ratified as a permanent category after the 2012 awards.
Blindsight is a hard science fiction novel by Canadian writer Peter Watts, published by Tor Books in 2006.
 It garnered nominations for a Hugo Award for Best Novel, a John W. Campbell Memorial Award for Best Science Fiction Novel, and a Locus Award for Best Science Fiction Novel.
 The novel follows a crew of astronauts sent out as the third wave, following two series of probes, to investigate a trans-Neptunian Kuiper belt comet dubbed 'Burns-Caulfield' that has been found to be transmitting an unidentified radio signal to an as-yet unknown destination elsewhere in the solar system, followed by their subsequent first contact.
 The novel explores questions of identity, consciousness, free will, artificial intelligence, neurology, game theory as well as evolution and biology.
 "Blindsight" is available online under a Creative Commons license.
 Its sequel "Echopraxia" came out in 2014.