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 	<div class="further-reading" style="float:right;width:30%;margin-left:15px;">
 		<h4>Further reading</h4>
-		<p>Slocum et al. (2008) Thematic Cartography and Visualization. Pentice Hall</p>
+		<p>Slocum et al. (2008) Thematic Cartography and Visualization. Prentice Hall</p>
 		<p>ColorBrewer: An online tool for selecting color schemes for maps. The Cartographic Journal 40(1): 27-37.</p> 
 		<p><a href="http://en.wikipedia.org/wiki/Color_theory" target="_blank">Color Theory (wikipedia)</a></p>
 	</div>
@@ -11,4 +11,4 @@ <h4>Further reading</h4>
 <p>Many cartographers advise that you use five to seven classes for a choropleth map. Isoline maps, or choropleth maps with very regular spatial patterns, can safely use more data classes because similar colors are seen next to each other, making them easier to distinguish.</p>
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