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diff --git a/docs/examples/tracing/Square.java b/docs/examples/tracing/Square.java
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+/*
+
+Copyright (c) Xerox Corporation 1998-2002.  All rights reserved.
+
+Use and copying of this software and preparation of derivative works based
+upon this software are permitted.  Any distribution of this software or
+derivative works must comply with all applicable United States export control
+laws.
+
+This software is made available AS IS, and Xerox Corporation makes no warranty
+about the software, its performance or its conformity to any specification.
+
+|<---            this code is formatted to fit into 80 columns             --->|
+|<---            this code is formatted to fit into 80 columns             --->|
+|<---            this code is formatted to fit into 80 columns             --->|
+
+*/
+
+package tracing;
+
+/**
+ *
+ * Square is a 2D shape. It extends the TwoDShape class with the side
+ * variable, and it implements TwoDShape's abstract methods for 
+ * correctly computing a square's area and distance.
+ *
+ */
+public class Square extends TwoDShape {
+    protected double s;    // side
+
+    /*
+     * All sorts of constructors
+     */
+    public Square(double x, double y, double s) {
+        super(x, y); this.s = s;
+    }
+
+    public Square(double x, double y) {
+        this(x, y, 1.0);
+    }
+
+    public Square(double s) {
+        this(0.0, 0.0, s);
+    }
+
+    public Square() {
+        this(0.0, 0.0, 1.0);
+    }
+
+    /**
+     * Returns the perimeter of this square
+     */
+    public double perimeter() {
+        return 4 * s;
+    }
+
+    /**
+     * Returns the area of this square
+     */
+    public double area() {
+        return s*s;
+    }
+
+    /**
+     * This method overrides the one in the superclass. It adds some
+     * circle-specific information.
+     */
+    public String toString() {
+        return ("Square side = " + String.valueOf(s) + super.toString());
+    }
+}