Allen, J. (1924). State of Washington showing state highways and principal county roads. Shell Oil Company of California.
Cita Chicago Style (17a ed.)Allen, James. State of Washington Showing State Highways and Principal County Roads. California: Shell Oil Company of California, 1924.
Cita MLA (8a ed.)Allen, James. State of Washington Showing State Highways and Principal County Roads. Shell Oil Company of California, 1924.
Precaución: Estas citas no son 100% exactas.