Self-made image, converted from the following vector PostScript source code:

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70.7107 100 lineto 100 100 79 180 270 arc 100 70.7107 lineto
-70.7107 -100 lineto -100 -100 79 0 90 arc closepath gsave 0
setgray 30 setlinewidth stroke grestore .2 .77 .32 setrgbcolor
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grestore 4{0 setgray 30 setlinewidth 100 70.7107 moveto -48 -48
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.77 .32 setrgbcolor 10.54 setlinewidth 100 70.7107 moveto -49
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90 rotate}repeat 2{0 setgray 30 setlinewidth 100 -70.7107
moveto -82 82 rmoveto 23 -23 rlineto stroke .2 .77 .32
setrgbcolor 10.54 setlinewidth 100 -70.7107 moveto -83 83
rmoveto 25 -25 rlineto stroke 180 rotate}repeat showpage
%EOF