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Brenan, Gerald A History of the House of Percy, From the Earliest Times Down to the Present Century; Volume 1
 Brenan, Gerald A History of the House of Percy, From the Earliest Times Down to the Present Century; Volume 1
Sanford, Percy Gerald Nitro-Explosives: A Practical Treatise Concerning the Properties, Manufacture, and Analysis of Nitrated Substances, Including the Fulminates, Smokeless Powders, and Celluloid
 Sanford, Percy Gerald Nitro-Explosives: A Practical Treatise Concerning the Properties, Manufacture, and Analysis of Nitrated Substances, Including the Fulminates, Smokeless Powders, and Celluloid
Sanford, Percy Gerald