This subject fascinates me. I've seen a couple of documentaries, but if anyone has more recommendations, please do share! Great post, by the way!
http://www.astonishinglegends.com/al-podcasts/2018/5/26/ep-1...
http://www.astonishinglegends.com/al-podcasts/2018/06/10/ep-...
http://www.astonishinglegends.com/al-podcasts/2018/06/17/ep-...