Simple knotwork cross assembled from straight lines and 45° circular arcs, with 12 crossings (11 significant in terms of knot theory).  Topologically equivalent to an interlaced {11/2} star polygon (see http://katlas.math.toronto.edu/wiki/Image:112-star-polygon-undecagram2.png ).
Self-made image, converted from the following PostScript vector source code:

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%EOF
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