A new study from a peer-reviewed academic journal says that classic children’s books written by Dr. Seuss are racist.

According to a report from The College Fix, the peer-reviewed academic journal Research on Diversity in Youth Literature published an article in February that argued that books by Dr. Seuss are racist.

The paper was authored by Katie Ishizuka of The Conscious Kid Library and Ramón Stephens, a doctoral student at the University of California, San Diego. The paper details Dr. Seuss’s early history, which included the publication of racially insensitive cartoons. Dr. Suess also supported the internment of Japanese-Americans during World War II.