As Hans was giving Li Du an explanation about the toys, he also showed him the information he found on the internet.
That information was from the autobiography of A.C. Gilbert, owner of Gilbert Toys. He wrote in his autobiography:
"The educational toy I am most proud of is the Gilbert U-238 Atomic Energy Laboratory. Its product development was supported by the government and greatly helped the public understand the principles of atomic energy. It was very meaningful and significant. We also received assistance from the country's top nuclear physicists and got counseling from the Massachusetts Institute of Technology."