By Amanda Watts and Leah Asmelash, CNN

(CNN) -- Six Dr. Seuss books will no longer be published because they "portray people in ways that are hurtful and wrong," the business that preserves the author's legacy said.

The titles are:

"And to Think That I Saw It on Mulberry Street"

"If I Ran the Zoo"

"McElligot's Pool"

"On Beyond Zebra!"

"Scrambled Eggs Super!"

"The Cat's Quizzer"

In a statement, Dr. Seuss Enterprises said it made the decision after consulting educators and reviewing its catalog.

"Ceasing sales of these books is only part of our commitment and our broader plan to ensure Dr. Seuss Enterprises's catalog represents and supports all communities and families," it said.

The announcement was made Tuesday, the birthday of the famed children's book author.

Seuss, born Theodor Seuss Geisel, is one of the best-known authors in the world, the man behind beloved classics like "The Cat in the Hat," "Green Eggs and Ham" and "How the Grinch Stole Christmas," among others. Over 650 million copies of his books have been sold worldwide, the Washington Post reported in 2015.

But Dr. Seuss had a long history of publishing racist and anti-Semitic work, spanning back to the 1920s when he was a student at Dartmouth College. There, Dr. Seuss once drew Black boxers as gorillas and perpetuated Jewish stereotypes by portraying Jewish characters as financially stingy, according to a study published in the journal "Research on Diversity in Youth Literature."

That study, published in 2019, examined 50 books by Dr. Seuss and found 43 out of the 45 characters of color have "characteristics aligning with the definition of Orientalism," or the stereotypical, offensive portrayal of Asia. The two "African" characters, the study says, both have anti-Black characteristics.

Two specific examples, according to the study, are found in the books "The Cat's Quizzer: Are YOU Smarter Than the Cat in the Hat?" and "If I Ran the Zoo."

"In ("The Cat's Quizzer"), the Japanese character is referred to as 'a Japanese,' has a bright yellow face, and is standing on what appears to be Mt. Fuji," the authors wrote.

Regarding "If I Ran the Zoo," the study points out another example of Orientalism and White supremacy.

"The three (and only three) Asian characters who are not wearing conical hats are carrying a White male on their heads in 'If I Ran the Zoo.' The White male is not only on top of, and being carried by, these Asian characters, but he is also holding a gun, illustrating dominance. The text beneath the Asian characters describes them as 'helpers who all wear their eyes at a slant' from 'countries no one can spell,'" the study authors wrote.

The study also argues that since the majority of human characters in Dr. Seuss' books are White, his works -- inadvertently or not -- center Whiteness and thus perpetuate White supremacy.

Separating Seuss from children's literature

Earlier this week, a school district in Virginia made headlines for allegedly banning books by Dr. Seuss.

But Loudoun County Public Schools (LCPS), located in Ashburn, said it is not banning books by the famous children's author -- it's just discouraging a connection between "Read Across America Day," which was created to get kids excited about reading, and Dr. Seuss' birthday. Both fall on March 2, and have often been "historically connected" to each other, the district said in a statement.

"Research in recent years has revealed strong racial undertones in many books written/illustrated by Dr. Seuss," LCPS said in its statement, which links to a School Library Journal article from 2018 about the National Education Association focusing its Read Across America efforts "on Diversity Not Dr. Seuss."