Loss Prevention of personal library during the Holocaust - Pressburg

In a copy of Anshe Shem of Buber, I came across a stamp stating : ספרי' של יוסף אייכלר פרעסבורג
הספר הזה אם אינו ברשות בעליו מצוה להחזירו כי נגזל או נאבד ע"י הגזירות בשנת התש"ב לפ"ק "
"From the library of Yosef Eichler, Pressburg
This book, if not in the procession of it's owner, it shall be a mitzvah to return it, as it was stolen or lost during the calamities of the year 5742 (1941-42)"

Y. Eichler seeing the approaching devastation seems to have went ahead and stamped his books with this such in hopes of being able to reclaim them in better days.

"Following the creation of an independent Slovak State in March 1939, the Jews of Bratislava were subjected to discriminatory practices and persecution. By the 1st of March 1942, nearly half of the city’s Jews had been evicted, and dispersed in smaller towns across the country. During 1942 many of the Jews of Bratislava were deported to the death camps in Poland.
During the war the city was home to the Bratislava Working Group, which was devoted to rescuing Jews. The group’s efforts, however, came to naught and most Slovakian Jews were murdered in the Holocaust."

Hat-tip: YItzchak Stroh