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- Penson, S.R.G.1
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- Poole Brothers1
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- Rand McNally and Company, engravers.1
- Ranney, Adolphus.1
- Reid, John (Publisher)1
- Robinson, Eugene1
- Roeser, C. (Charles), compiler.1
- Shaler, Nathaniel Southgate, 1841-19061
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- Smith, Shirley Wheeler, 1875-19591
- Society for the Diffusion of Useful Knowledge (Great Britain)1