Oklahoma Labor Unit (Oklahoma City, Okla.), Vol. 8, No. 13, Ed. 1 Saturday, September 18, 1915, newspaper, September 18, 1915; (https://gateway.okhistory.org/ark:/67531/metadc157269/m1/1/: accessed September 19, 2017), University of North Texas Libraries, The Gateway to Oklahoma History, gateway.okhistory.org; .