Sources:

F.W. Woolworth Company Annual Reports

McCrory Stores Company Annual Reports

McCrory Corporation Annual Reports
Kresge Company Annual Reports

Kmart Corporation Annual Reports

G.C. Murphu Company Annual Reports

J.J. Newberry Company Annual Reports

S.H. Kress & Company Annual Reports

Genesco, Incorporated Annual Reports

Neisner Brothers, Incorporated Annual Reports

V.J. Elmore Stores, Incorporated Annual Reports

W.T. Grant Company Annual Reports
Google News Archive

New York State Historic Newspapers

California Digital Newspaper Collection

Colorado Historic Newspaper Collection
Chronicling America - Historic American Newspapers / Library of Congress
The Boston Public Library

The Oklahoman
http://thewoolworthbuilding.com
http://www.gcmurphy.com
http://www.fundinguniverse.com
http://www.dollargeneral.com
https://aboutus.dollargeneral.com
http://www.familydollar.com

Various articles on Wikipedia