The principal differences between the 1950 Standard specifications and the 1957 Standard specifications.
APA Citation
Michigan. State Highway Dept. (1957). The principal differences between the 1950 Standard specifications and the 1957 Standard specifications. [Lansing? Mich..
MLA Citation
Michigan. State Highway Dept. The Principal Differences Between the 1950 Standard Specifications And the 1957 Standard Specifications. [Lansing? Mich., 1957.
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