Measure link https://www.aceee.org/sites/default/files/pdfs/Load%20Factor%20Smart%20Freight%… https://www.sciencedirect.com/science/article/pii/S1877042812027358 https://railroads.dot.gov/sites/fra.dot.gov/files/fra_net/2925/Comparative_Eval… https://www.diva-portal.org/smash/get/diva2:1651031/FULLTEXT01.pdf