Legend (as passed down verbally) has it that a Japanese officer had all the books in the Medical Library stamped with his troop's seal. As a result, no other Japanese dared to destroy or damage them. This act on the officer's part kept the Medical Library collection intact through World War II. The seal has been translated as :
Oka dai 9420-butai tosho sei'in (Japanese) or Seal of Troop 9420 Library