Ballard, M., & Mathias, P. (1971). Revolutions and steam engines 1775 - 1815. Methuen.
Chicago Edition CitationBallard, Martin, i Peter Mathias. Revolutions and Steam Engines 1775 - 1815. London: Methuen, 1971.
Cita MLABallard, Martin, i Peter Mathias. Revolutions and Steam Engines 1775 - 1815. Methuen, 1971.
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