History of northern Wisconsin: containing an account of its settlement, growth, development, and resources, an extensive sketch of its counties, cities, towns and villages, their improvements, industries, manufactories, biographical sketches, portraits of prominent men and early settlers, views of county seats, etc. Chicago: Western Historical Co., 1881. p.1148

H. C. Gustavus & Co., flour-mills (firm composed of H.C. Gustavus and Casper Smith), commenced business in 1876. They employ fifteen men and turn our 125 barrels of flour daily. H.C. Gustavus, of the firm of Gustavus & Co., flour-mills, was born in Brandenburg, Prussia, Sept. 11, 1846; came to the United State with his parents in 1851; located in Winnebago Co., Wis., and followed farming up to 1867, when he moved to Neenah and engaged in the manufacture of flour, the firm being Gustavus & Son. In 1876 he came to Oshkosh and formed the present firm. He was married in Neenah Oct. 14, 1868, to Miss Eliza Schmidt. They have two children- Henry and Louisa. Mr. Gustavus is a member of the I.O.O.F. and of the Turnverein and Sharpshooters