diff --git a/arrays_strings/unique_chars/unique_chars_challenge.ipynb b/arrays_strings/unique_chars/unique_chars_challenge.ipynb
index 4e03a34..e6b9049 100644
--- a/arrays_strings/unique_chars/unique_chars_challenge.ipynb
+++ b/arrays_strings/unique_chars/unique_chars_challenge.ipynb
@@ -64,7 +64,7 @@
    "source": [
     "## Algorithm\n",
     "\n",
-    "Refer to the [solution notebook](#).  If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start."
+    "Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/arrays_strings/compress/unique_chars_solution.ipynb).  If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start."
    ]
   },
   {
@@ -142,7 +142,7 @@
    "source": [
     "## Solution Notebook\n",
     "\n",
-    "Review the [solution notebook](#) for a discussion on algorithms and code solutions."
+    "Review the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/arrays_strings/compress/unique_chars_solution.ipynb) for a discussion on algorithms and code solutions."
    ]
   }
  ],