Donald J. Sobol, author of the "Encyclopedia Brown" series that captured the imaginations of children worldwide, died Monday. He was 87.
Circumstances of Sobol's death were not released, but Publishers Weekly tweeted about the author's passing.
"'Encyclopedia Brown' creator Donald J. Sobol has died, at age 87," Publishers Weekly's Twitter account said.
Sobol's most famous series of books followed the adventures of boy detective Leroy 'Encyclopedia' Brown, who sometimes assisted his detective father at crime scenes, reported the International Business Times. Solutions to each of Brown's cases — littered with witty puns and other verbal jokes — were printed on the back of each book, although readers were encouraged to solve them on their own.
According to GalleyCat, Sobol also wrote the "Two Minute Mystery" series from 1959 to 1968. "Encyclopedia Brown" was launched in 1963, and the books are still available from Penguin publishing group.
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Sobol's death rocked the Twitterverse, with many users tweeting about their love of his books and the series' influence on their childhoods.
Twitter user Tim deBord tweeted: "Loved those books in my youth. Thanks for the adventures, Donald."
"RIP Donald J. Sobol, creator of the first great love of my life: Sally Kimball," wrote Twitter user Angus Johnston about the boy detective's best friend who helped him solve mysteries.
Jordan Lakin tweeted: "rip donald j sobol. just today picked up an encyclopedia brown for the 1st time in years & used it in my class. #quality."
"Encyclopedia Brown" inspired everything from a comic strip, a TV show, a Simpson‘s parody, an Onion article and an awesome list of the 10 Most Ridiculously Difficult Encyclopedia Brown Mysteries, according to GalleyCat.
The book publishing news site also quoted Sobol as once saying: "Readers constantly ask me if Encyclopedia is a real boy. The answer is no … He is, perhaps, the boy I wanted to be — doing the things I wanted to read about but could not find in any book when I was ten."