LONDON (AP) — British writer Allan Ahlberg, author of more than 150 children’s books including classics like “Eat Peach Pear Plum” and “The Jolly Postman,” has died, his publisher said Friday. He was 87.

Penguin Random House said Ahlberg died on Tuesday. It did not give a cause of death.

Ahlberg’s books introduced generations of young children to reading through simple rhymes, sharp observation and gentle humor. Many were co-created with his illustrator wife, Janet Ahlberg, who died in 1994.

“Peepo!” (1981) gave a baby’s-eye-view of the world and was interactive in a delightfully analogue way, with peep-holes in the pages to spy the next scenes.

“The Jolly Postman” (1986) was even more inventive, incorporating postcards and letters in envelopes for children to engage with while they followed a letter-carrier delivering mail to fairy tale characters. Penguin Random House said it “pushed at the boundaries of what it is possible for a book to be.”

Ahlberg also wrote books of jokes, including “The Ha Ha Bonk Book,” and poetry for primary school-age children, including “Please Mrs. Butler” and “Heard it in the Playground.”

Born in 1938 and raised by adoptive parents in a working-class home in OIdbury, central England, Ahlberg worked as a “postman, plumber’s mate and grave digger,” according to his publisher, before becoming a teacher. He met Janet at teacher training college and the couple’s first book, “Here are the Brick Street Boys,” was published in 1975.

Then came ”’Burglar Bill” in 1977, about a burglar who steals a baby, and “Eat Peach Pear Plum” in 1978, with its pages of intricately drawn nursery-rhyme characters. It won Janet the Kate Greenaway Medal for illustration, one of the most prestigious awards in children’s publishing. “The Jolly Christmas Postman” won the same prize in 1991.

“Just because a book is tiny and its readers are little doesn’t mean it can’t be perfect,” Ahlberg told The Guardian in 2006. “On its own scale, it can be as good as Tolstoy or Jane Austen.”

The couple’s work brought huge commercial success. “The Jolly Postman” has sold more than 6 million copies. The “Funnybones” series about a playful skeleton household was adapted for television.

After Janet died of cancer at just 50 years old, Ahlberg worked with illustrators including Raymond Briggs and his daughter, Jessica Ahlberg.

For adults, he wrote a tribute to his wife, “Janet’s Last Book,” and autobiographical volumes “The Boyhood of Burglar Bill” and “The Bucket.”

In 2014, he turned down a lifetime achievement award from the BookTrust charity because it was sponsored by Amazon, which was facing criticism over its tax arrangements.

Francesca Dow, head of children’s literature at Penguin Random House, said Ahlberg’s books have been described as “mini masterpieces.”

“He knew that making it perfect for children matters, and above all that the very best stories for children last forever,” Dow said. “Allan’s are some of the very best – true classics, which will be loved by children and families for years to come.”

Ahlberg is survived by his second wife, Vanessa Clarke, his daughter and two stepdaughters.