Howarth, S. (1997). A century in oil: The "Shell" Transport and Trading Company 1897-1997. Weidenfeld & Nicolson.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रHowarth, Stephen. A Century in Oil: The "Shell" Transport and Trading Company 1897-1997. London: Weidenfeld & Nicolson, 1997.
एमएलए (8वां संस्करण) प्रशस्ति पत्रHowarth, Stephen. A Century in Oil: The "Shell" Transport and Trading Company 1897-1997. Weidenfeld & Nicolson, 1997.
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