diff --git a/pom.xml b/pom.xml
index 9aac22c..3d72263 100644
--- a/pom.xml
+++ b/pom.xml
@@ -79,7 +79,7 @@
         <dependency>
             <groupId>org.choco-solver</groupId>
             <artifactId>choco-solver</artifactId>
-            <version>4.10.6</version>
+            <version>4.10.10</version>
         </dependency>
         <dependency>
             <groupId>guru.nidi</groupId>
diff --git a/src/test/java/cryptator/Failing.java b/src/test/java/cryptator/Failing.java
index 2cf2a66..63a093a 100644
--- a/src/test/java/cryptator/Failing.java
+++ b/src/test/java/cryptator/Failing.java
@@ -75,4 +75,15 @@ public void testExpression2() {
         assertTrue(true);
     }
 
+    @Test
+    public void testPrinterError2() throws CryptaParserException, CryptaModelException, CryptaSolverException {
+        // https://mathworld.wolfram.com/PrintersErrors.html
+        t.testUNIQUE("3^4*425 = 34425");
+    }
+
+    @Test
+    public void testBarker4() throws CryptaParserException, CryptaModelException, CryptaSolverException {
+        t.testUNIQUE("copper*neon=iron*silver");
+    }
+
 }
diff --git a/src/test/java/cryptator/ProductTest.java b/src/test/java/cryptator/ProductTest.java
new file mode 100644
index 0000000..e57c762
--- /dev/null
+++ b/src/test/java/cryptator/ProductTest.java
@@ -0,0 +1,108 @@
+/**
+ * This file is part of cryptator, https://github.com/arnaud-m/cryptator
+ *
+ * Copyright (c) 2022, Université Côte d'Azur. All rights reserved.
+ *
+ * Licensed under the BSD 3-clause license.
+ * See LICENSE file in the project root for full license information.
+ */
+package cryptator;
+
+import org.chocosolver.solver.Model;
+import org.chocosolver.solver.Solver;
+import org.chocosolver.solver.variables.IntVar;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class ProductTest {
+
+    private Model model;
+    private IntVar copper, neon, iron, silver, result;
+
+    @Before
+    /***
+     * Tests if choco can solve "copper*neon=iron*silver" via various way of writing constraints
+     */
+    public void setup(){
+        model = new Model("copper*neon=iron*silver");
+        copper = model.intVar("copper",100000,999999);
+        neon = model.intVar("neon",1000,9999);
+        iron = model.intVar("iron",1000,9999);
+        silver = model.intVar("silver",100000,999999);
+        model.allDifferent(new IntVar[]{copper,neon,iron,silver}).post();
+    }
+    
+    public void setupResult(int factor) {
+      //result is an intermediary to compare copper*neon and iron*silver
+      //all test would fail if factor = 1.
+        result = model.intVar("result",0, factor * IntVar.MAX_INT_BOUND);
+    }
+    
+    public void solve(int solutionCount) {
+        Solver solver = model.getSolver();
+        System.out.println(model);
+        solver.printVersion();
+        solver.showStatistics();
+        solver.showSolutions();
+        solver.findSolution();
+        Assert.assertEquals(solutionCount, solver.getSolutionCount());
+    }
+        
+
+    @Test
+    /***
+     * Using times directly to make our constraint
+     * will fail to find any solution because value needed is greater than the result's upper bound.
+     */
+    public void model1NoSol(){
+        setupResult(1);
+        model.times(copper, neon, result).post();
+        model.times(silver, iron, result).post();
+        solve(0);
+    }
+    
+    @Test
+    @Ignore
+    /***
+     * Working version of the previous test.
+     */
+    public void model1(){
+        setupResult(10);        
+        model.times(copper, neon, result).post();
+        model.times(silver, iron, result).post();
+        solve(1);
+    }
+    @Test
+    @Ignore
+    /***
+     * Creating a model using arithm instead of times directly.
+     */
+    public void model2(){
+        setupResult(10);        
+        model.arithm(copper, "*",neon,"=",result).post();
+        model.arithm(iron, "*",silver,"=",result).post();
+        solve(1);
+    }
+    @Test
+    @Ignore
+    /***
+     * Creating a model using the operators function given by IntVar
+     */
+    public void model3(){
+        setupResult(10);        
+        copper.mul(neon).eq(result).post();
+        iron.mul(silver).eq(result).post();
+        solve(1);
+    }
+    @Test
+    @Ignore
+    /***
+     * Creating a model using the operators function given by IntVar without using result as an intermediary
+     */
+    public void model4(){
+        copper.mul(neon).eq(iron.mul(silver)).post();
+        solve(1);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/cryptator/SolverTest.java b/src/test/java/cryptator/SolverTest.java
index 526ea68..9bff07e 100644
--- a/src/test/java/cryptator/SolverTest.java
+++ b/src/test/java/cryptator/SolverTest.java
@@ -358,10 +358,7 @@ public void testBarker3() throws CryptaParserException, CryptaModelException, Cr
         t.testUNIQUE("pear+plum+apple+grape+lemon=orange");
     }
 
-    @Test
-    public void testBarker4() throws CryptaParserException, CryptaModelException, CryptaSolverException {
-        t.testUNIQUE("copper*neon=iron*silver");
-    }
+
 
     @Test
     public void testBarker5() throws CryptaParserException, CryptaModelException, CryptaSolverException {
@@ -386,11 +383,7 @@ public void testPow1() throws CryptaParserException, CryptaModelException, Crypt
         t.testSAT("A = B ^ C", 2);
     }
 
-    @Test
-    public void testPrinterError2() throws CryptaParserException, CryptaModelException, CryptaSolverException {
-        // https://mathworld.wolfram.com/PrintersErrors.html
-        t.testUNIQUE("3^4*425 = 34425");
-    }
+
 
     @Test
     public void testDivision1() throws CryptaParserException, CryptaModelException, CryptaSolverException {
diff --git a/src/test/resources/cryptarithms-barker.txt b/src/test/resources/cryptarithms-barker.txt
index 12905f7..b5384a2 100644
--- a/src/test/resources/cryptarithms-barker.txt
+++ b/src/test/resources/cryptarithms-barker.txt
@@ -95,7 +95,7 @@ gold*iron=lead*tin
 gold*neon=lead*zinc
 ## FIXME iron*radium=neon*sodium
 argon*tin=iron*zinc
-copper*neon=iron*silver
+## FIXME copper*neon=iron*silver
 ## Colours of the Rainbow
 green+violet=indigo
 red+green+orange=yellow