Michigan Department of Transportation (April 23, 2006). National Highway System, Michigan(PDF) (Map). Scale not given. Lansing: Michigan Department of Transportation. Archived from the original(PDF) on October 4, 2012. Retrieved October 7, 2008.
Michigan Department of Transportation (2009). Statewide AADT Map(PDF) (Map). Scale not given. Lansing: Michigan Department of Transportation. Retrieved February 28, 2011.
Michigan Department of Transportation (2009). Commercial Statewide AADT Map(PDF) (Map). Scale not given. Lansing: Michigan Department of Transportation. Retrieved February 28, 2011.
Garner, Dawn (November 3, 2003). "New M-73 Bridge Opens to Motorists" (Press release). Michigan Department of Transportation. Archived from the original on January 1, 2011. Retrieved February 28, 2011.
michiganology.org
Michigan State Highway Department & Rand McNally (May 15, 1937). Official Michigan Highway Map (Map) (Summer ed.). [c. 1:850,000]. Lansing: Michigan State Highway Department. § D3. OCLC12701143. Retrieved October 17, 2019 – via Michigan History Center.
Michigan State Highway Department & Rand McNally (December 1, 1937). Official Michigan Highway Map (Map) (Winter ed.). [c. 1:850,000]. Lansing: Michigan State Highway Department. § D3. OCLC12701143. Retrieved October 17, 2019 – via Michigan History Center.
Michigan Department of Transportation (April 23, 2006). National Highway System, Michigan(PDF) (Map). Scale not given. Lansing: Michigan Department of Transportation. Archived from the original(PDF) on October 4, 2012. Retrieved October 7, 2008.
Garner, Dawn (November 3, 2003). "New M-73 Bridge Opens to Motorists" (Press release). Michigan Department of Transportation. Archived from the original on January 1, 2011. Retrieved February 28, 2011.
Michigan State Highway Department & Rand McNally (May 15, 1937). Official Michigan Highway Map (Map) (Summer ed.). [c. 1:850,000]. Lansing: Michigan State Highway Department. § D3. OCLC12701143. Retrieved October 17, 2019 – via Michigan History Center.
Michigan State Highway Department & Rand McNally (December 1, 1937). Official Michigan Highway Map (Map) (Winter ed.). [c. 1:850,000]. Lansing: Michigan State Highway Department. § D3. OCLC12701143. Retrieved October 17, 2019 – via Michigan History Center.
worldcat.org
Michigan Department of Transportation (2010). Uniquely Michigan: Official Department of Transportation Map (Map). c. 1:975,000. Lansing: Michigan Department of Transportation. § D3. OCLC42778335, 639960603.