diff --git a/strassnitzky_formula.tex b/strassnitzky_formula.tex
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+++ b/strassnitzky_formula.tex
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+\documentclass{standalone}
+\usepackage{tikz}
+
+\title{Strassnitzky's formula}
+\begin{document}
+	\begin{tikzpicture}
+		\draw[help lines, color=gray!30, dashed] (0,0) grid (10,8);
+		\draw[-,fill=gray, opacity=0.5] (0,0) -- (10,0) -- (10,2) -- (0,0);
+		\draw[-,fill=gray!50!white, opacity=0.5] (0,0) -- (10,2) -- (9,7) -- (0,0);
+		\draw[-,fill=gray, opacity=0.5] (0,0) -- (9,7) -- (8,8) -- (0,0);
+		\draw[-,thick] (0,0) -- (8,0) -- (8,8) -- (0,0);
+		\draw[rotate=-45] (0,1) arc (90:45:1);
+		\draw[-] (9.8,0) -- (9.8,0.2) -- (10,0.2);
+		\draw[-] (7.8,0) -- (7.8,0.2) -- (8,0.2);
+		\coordinate(A) at (10,2);
+		\coordinate(B) at (8,8);
+		\draw[-,rotate around={13:(A)}] (10,2.2) -- (9.8,2.2) -- (9.8,2);
+		\draw[-,rotate around={315:(B)}] (8.2,8) -- (8.2,7.8) -- (8,7.8);
+	\end{tikzpicture}
+\end{document}