diff --git a/experiments/reduce-cycle.py b/experiments/reduce-cycle.py
index 4023f0084df7f7934d9ed4a7908317521c7b8068..097b4438eee3c4a0fcf19f0fee6552b66e2630fa 100755
--- a/experiments/reduce-cycle.py
+++ b/experiments/reduce-cycle.py
@@ -2,7 +2,9 @@
 
 """
 Application of Theorem 6.12 to triangles, 4-cycles (Theorem 6.13)
-and 5.cycles (Theorem 6.14).
+and 5.cycles (Theorem 6.14). Note that the results are numeric
+calculation so it is necessary to review the system of equations
+by hand. (It is printed by the command-line parameter -v.)
 """
 
 import sys, os