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

%!
306 396 translate 1.85 dup scale 1.5 setlinewidth 1 setlinejoin/z 1 18 cos
div 100 mul def/x 18 sin z mul def/y 100 18 sin 100 mul 108 sin x mul add
sub x 100 div mul def/A{gsave -36 cos z mul -36 sin z mul moveto -72 cos z
mul -72 sin z mul lineto 0 0 lineto x 2 mul 0 lineto closepath gsave fill
grestore 0 setgray stroke grestore x 100 moveto x y add 18 sin 100 mul 108
sin x mul add lineto x y sub 18 sin 100 mul 108 sin x mul add lineto
closepath gsave fill grestore 0 setgray stroke}def .8 .1 .8 setrgbcolor A
72 rotate 0 .8 0 setrgbcolor A 72 rotate .875 0 0 setrgbcolor A 72 rotate
.1 .1 .925 setrgbcolor A 72 rotate .95 .9 0 setrgbcolor A showpage
%EOF