What does the above photograph commemorate and document?

Which of the following performers applied earl scruggs banjo technique to the dobro josh graves tony trishchka jerry douglas bela fleck

List as many characteristics as you can to describe each style realism and propaganda

In russian churches the number of domes usually matches the number of altars. but this church has only one altar dome, and 21 symbolic ones. what normal construction device does this church lack?