diff --git a/articles/Fourier transforms of images plus.maths.org/Fourier transforms of images plus.maths.org.pdf.txt b/articles/Fourier transforms of images plus.maths.org/Fourier transforms of images plus.maths.org.pdf.txt
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--- /dev/null
+++ b/articles/Fourier transforms of images plus.maths.org/Fourier transforms of images plus.maths.org.pdf.txt	
@@ -0,0 +1 @@
+https://web.archive.org/web/20230927155231/https://plus.maths.org/content/fourier-transforms-images
diff --git a/articles/Fourier transforms of images plus.maths.org/Fourier transforms of images plus.maths.org.xopp.xml b/articles/Fourier transforms of images plus.maths.org/Fourier transforms of images plus.maths.org.xopp.xml
new file mode 100644
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+rotated
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+
+Is it due to
+blackness
+introduced by
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+      <text font="Sans" size="12.00000000" x="503.66255960" y="45.26872994" color="#00c0ffff" ts="0" fn="">vertical line
+due to bricks
+it seems cf
+sin(x)</text>
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