WARSAW (JTA) — Employees of the Auschwitz-Birkenau State Museum discovered handwritten inscriptions in shoes belonging to children who were sent to the Nazi death camp in Poland.

The discoveries were made in the course of efforts to preserve the shoes on display at the museum.

One inscription identified a shoe as belonging to Amos Steinberg, who was born in Prague in 1938 and imprisoned with his parents in the Theresienstadt ghetto in 1942. He was later sent to Auschwitz.

“We can guess that it was most likely his mother who made sure that her child’s shoe was signed,” Hanna Kubik of the museum’s collections department said in a statement Tuesday announcing the findings. “The father was deported in another transport. We know that on October 10, 1944, he was transferred from Auschwitz to the Dachau camp. He was liberated in the Kaufering sub-camp.”

In another shoe, employees found documents in Hungarian with several names: Ackermann, Brávermann and Beinhorn.

“These people were probably deported to Auschwitz in the spring or summer of 1944 during the extermination of Hungarian Jews,” Kubik said. “I hope that more detailed research will reveal details about each individual.”

Vast quantities of children’s shoes are on display at Auschwitz, and the museum has been engaged in an ongoing effort to preserve them. Many historical artifacts have been found in this process, including letters, newspaper fragments and bank notes, some of which were used as lining or padding.

About 230,000 children are estimated to have been imprisoned in Auschwitz, the vast majority of whom perished there.