Some Surfaces with Zero Curvature in <svg     style="vertical-align:-0.45pt;width:67.875px;" id="M1" height="21.025" version="1.1" viewBox="0 0 67.875 21.025" width="67.875"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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<table>A flat surface defined by (<a href="https://static.hindawi.com/articles/jam/volume-2014/154294/figures/#EEq5.4">52</a>) and (<a href="https://static.hindawi.com/articles/jam/volume-2014/154294/figures/#EEq5.5">55</a>).</table>

Journal of Applied Mathematics

fig2

Figure 2

Figure 2: Some Surfaces with Zero Curvature in <svg     style="vertical-align:-0.45pt;width:67.875px;" id="M1" height="21.025" version="1.1" viewBox="0 0 67.875 21.025" width="67.875"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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