Solomon, Brian (15 June 2016). "EMD DDA40X". The field guide to trains : locomotives and rolling stock. Minneapolis, Minnesota. p. 189. ISBN9780760349977. OCLC928614280.{{cite book}}: CS1 maint: location missing publisher (link)
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Solomon, Brian (15 June 2016). "EMD DDA40X". The field guide to trains : locomotives and rolling stock. Minneapolis, Minnesota. p. 189. ISBN9780760349977. OCLC928614280.{{cite book}}: CS1 maint: location missing publisher (link)