[Avodah] Rav Unno

[SBA]

From: "Meir Shinnar" <>
 Issur of kol isha only applies to the problem of saying davar
shebikdusha in its presence (tshuva of Rav Unno, the Rav of
Mannheim before the war, justifiying having choruses of girls
sing - arguing that this was ikkar hadin
>>

I tried to google 'Rabbi Unno', 'Rav Unno' and 'Unno Mannheim' 
but got zero results (as compared to 839 when 
googling "Meir Shinnar"...).

Am I the only person here who has never heard of him before?

And seriously, where CAN one find out more about him?

SBA