Circumstances of 1958 Stockholm recordings?

[Ethan Prater <prater@bway.net>]

I recently acquired the 2CD GG set on BIS, recorded in 1958.

What were the circumstances under which these recordings were made? Were
they performed live before an audience or taped for radio broadcast (or a
mix of the two)?

There's applause after one of the concertos, indicating a live performance,
but audience noise is absent in some of the others.

Many thanks for any input,

-Ethan
--
Ethan Evan Prater
prater@bway.net