diff --git a/tikz/3d-gradient-cos/3d-gradient-cos.png b/tikz/3d-gradient-cos/3d-gradient-cos.png
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Binary files /dev/null and b/tikz/3d-gradient-cos/3d-gradient-cos.png differ
diff --git a/tikz/3d-gradient-cos/3d-gradient-cos.tex b/tikz/3d-gradient-cos/3d-gradient-cos.tex
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+++ b/tikz/3d-gradient-cos/3d-gradient-cos.tex
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+\documentclass{article}
+\usepackage[pdftex,active,tightpage]{preview}
+\setlength\PreviewBorder{2mm}
+\usepackage{pgfplots}
+\usepgfplotslibrary{patchplots}
+
+\begin{document}
+\begin{preview}
+\pgfplotsset{
+    colormap={whitered}{
+        color(0cm)=(white);
+        color(1cm)=(orange!75!red)
+    }
+}
+\begin{tikzpicture}
+    \begin{axis}[
+    colormap name=whitered,
+    width=15cm,
+    view={45}{45},
+    enlargelimits=false,
+    grid=major,
+    domain=-90:90,
+    y domain=-90:90,
+    % ymode=log,
+    samples=46, %57 : TeX capacity exceeded, sorry [main memory size=3000000].
+                % see also http://tex.stackexchange.com/a/7954/5645
+    % zlabel=f,
+    %colorbar,
+    %colorbar style={
+    %    at={(-0.1,0)},
+    %    anchor=south west,
+    %    height=0.25*\pgfkeysvalueof{/pgfplots/parent axis height},
+    %    title={$f(x,y)$}
+    %}
+    ]
+      %\addplot3[patch,patch type=bilinear,mesh,black] {0};
+      \addplot3[blue,/pgfplots/quiver,
+        quiver/u=4 * sin(x) * cos(x) * (cos(x)^2 + cos(y)^2),
+        quiver/v=4 * sin(y) * cos(y) * (cos(x)^2 + cos(y)^2),
+        quiver/w=0,
+        quiver/scale arrows=4,
+        -stealth,samples=15] {-4};
+      \addplot3[surf,opacity=0.9] {-(cos(x)^2 + cos(y)^2)^2};
+    \end{axis}
+\end{tikzpicture}
+\end{preview}
+\end{document}
diff --git a/tikz/3d-gradient-cos/Makefile b/tikz/3d-gradient-cos/Makefile
new file mode 100644
index 0000000..4720ea7
--- /dev/null
+++ b/tikz/3d-gradient-cos/Makefile
@@ -0,0 +1,35 @@
+SOURCE = 3d-gradient-cos
+DELAY = 80
+DENSITY = 300
+WIDTH = 512
+
+make:
+	pdflatex $(SOURCE).tex -output-format=pdf
+	make clean
+
+clean:
+	rm -rf  $(TARGET) *.class *.html *.log *.aux *.data *.gnuplot
+
+gif:
+	pdfcrop $(SOURCE).pdf
+	convert -verbose -delay $(DELAY) -loop 0 -density $(DENSITY) $(SOURCE)-crop.pdf $(SOURCE).gif
+	make clean
+
+png:
+	make
+	make svg
+	inkscape $(SOURCE).svg -w $(WIDTH) --export-png=$(SOURCE).png
+
+transparentGif:
+	convert $(SOURCE).pdf -transparent white result.gif
+	make clean
+
+svg:
+	make
+	#inkscape $(SOURCE).pdf --export-plain-svg=$(SOURCE).svg
+	pdf2svg $(SOURCE).pdf $(SOURCE).svg
+	# Necessary, as pdf2svg does not always create valid svgs:
+	inkscape $(SOURCE).svg --export-plain-svg=$(SOURCE).svg
+	rsvg-convert -a -w $(WIDTH) -f svg $(SOURCE).svg -o $(SOURCE)2.svg
+	inkscape $(SOURCE)2.svg --export-plain-svg=$(SOURCE).svg
+	rm $(SOURCE)2.svg
diff --git a/tikz/3d-gradient-cos/README.md b/tikz/3d-gradient-cos/README.md
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--- /dev/null
+++ b/tikz/3d-gradient-cos/README.md
@@ -0,0 +1,3 @@
+Compiled example
+----------------
+![Example](3d-gradient-cos.png)