Spider Covers and Their Applications

<table>(a) A digraph <svg height="11.75" id="M371" style="vertical-align:-0.23206pt" version="1.1" viewbox="0 0 12.4375 11.75" width="12.4375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>. </table>

International Scholarly Research Notices

Spider Covers and Their Applications

Figure 4