Do you know this ballad and the story behind it?

Hey, I’m doing my history research project on Unit 731. I really want to do it on this topic because it’s rarely spoken about and it’s extremely important.
I’ve found it very hard to find peer reviewed useful sources- especially primary sources. I also haven’t found any historians I could contact (if there are any).

Is anyone able to give a bit of help if they have any knowledge on the topic, or shiro ishii, or even on Japan the years leading up to it. It would be so greatly appreciated. Thanks!