He seems to have been reported in company E originally, but was reported in company A on 22 March 1864. He was transferred from company A to company D on 22 March 1864. [sources: 1, 2]
[I have not been able to identify this Bolen in Bates]
1 special order 23, HQ 91st PA, 22 March 1864
2 consolidated morning report, 22 March 1864 (Pri Bolen)