Map of the Illinois River Railroad / W.G. Wheaton, civil engineer.
MLA
Map of the Illinois River Railroad / W.G. Wheaton, Civil Engineer. J. Gemmell, Lith., 1860. https://collections.library.yale.edu/catalog/15814445.
APA, 6th edition
Map of the Illinois River Railroad / W.G. Wheaton, civil engineer. (1860). [Maps]. J. Gemmell, Lith., https://collections.library.yale.edu/catalog/15814445.