Key to Document Codes

XX.AH.XX.##
Documents from the Atlanta History Center

XX.LC.XX.##
Documents from the Library of Congress

XX.SS.XX.##
Documents reproduced within Secondary Sources

XX.GT.XX.##
Documents from Georgia Tech Library

XX.XX.NA.##
Newspaper Article

XX.XX.IM.##
Image, including photographs, illustrations, movie posters.

XX.XX.CR.##
Congressional Record

XX.XX.PM.##
Pamphlet

XX.XX.VT.##
Video Tape

XX.XX.SR.##
Sound Recording

XX.XX.TG.##
Telegraph

XX.XX.MG.##
Magazine article or cover

XX.XX.LE.##
Letter

XX.XX.XX.##
Numbers are continuous within the smallest possible category or subset (e.g., all letters from the Library of Congress logged by Ellen).