APA引文
Maps.com (Firm) & ebrary, Inc. (2000). Underground Railroad, 1860. Maps.com.
Chicago Style (17th ed.) Citation
Maps.com (Firm) and Inc ebrary. Underground Railroad, 1860. [S.l.]: Maps.com, 2000.
MLA引文
Maps.com (Firm) and Inc ebrary. Underground Railroad, 1860. Maps.com, 2000.
警告：這些引文格式不一定是100％准確.