APA-viite (7. p.)
Maps.com (Firm) & ebrary, Inc. (1999). Principal rivers, roads, and canals, 1840. Maps.com.
Chicago-viite (17. p.)
Maps.com (Firm) ja Inc ebrary. Principal Rivers, Roads, and Canals, 1840. [S.l.]: Maps.com, 1999.
MLA-viite (9. p.)
Maps.com (Firm) ja Inc ebrary. Principal Rivers, Roads, and Canals, 1840. Maps.com, 1999.
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