Statistics for occurrence #1 of “Doc” in year 1861, month March, day 21 of Rebellion Record: a Diary of American Events, Diary from December 17, 1860 - April 30, 1864:

... of the Confederate States of the South, delivered a speech at Savannah, Ga. It is intended to be a vindication of the new features in the contitution, which has been adopted for their government.--( Doc . 48.)
...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Doc 6,842 2,810 2 0 0 user votes
N. Y. Doc 1,108 0 0 0 0 user votes
Y. S. M. Doc 78 0 0 0 0 user votes
London Doc 4 0 0 0 0 user votes

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