diff --git a/control/statesp.py b/control/statesp.py
index f7fe6a3b5..d69f7d7d1 100644
--- a/control/statesp.py
+++ b/control/statesp.py
@@ -537,8 +537,9 @@ def zero(self):
             # from
             # https://dspace.mit.edu/bitstream/handle/1721.1/841/P-0802-06587335.pdf.
             # The QZ algorithm solves the generalized eigenvalue problem: given
-            # `L = [A, B; C, D]` and `M = [I_nxn 0]`, find all finite λ for
-            # which there exist nontrivial solutions of the equation `Lz - λMz`.
+            # `L = [A, B; C, D]` and `M = [I_nxn 0]`, find all finite lambda 
+            # for which there exist nontrivial solutions of the equation
+            # `Lz - lamba Mz`.
             #
             # The generalized eigenvalue problem is only solvable if its
             # arguments are square matrices.
diff --git a/control/tests/statesp_test.py b/control/tests/statesp_test.py
index 1677f6afe..fe1293fb5 100644
--- a/control/tests/statesp_test.py
+++ b/control/tests/statesp_test.py
@@ -42,7 +42,8 @@ def testPole(self):
 
         np.testing.assert_array_almost_equal(p, true_p)
 
-    def testZero(self):
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
+    def testMIMOZero_nonsquare(self):
         """Evaluate the zeros of a MIMO system."""
 
         z = np.sort(self.sys1.zero())