0.24 Ray Allen, An American Folk Opera? Triangulating Folkness Blackness and Americaness in Gershwin and Heyward's "Porgy and Bess", The Journal of American Folklore, 2004.

{ black african negro white }	0.24
{ song music musical folk }	0.19
{ cultural political national culture }	0.15
{ doe make world point }	0.09