diff --git a/sorting-searching/insertion-sort.ipynb b/sorting-searching/insertion-sort.ipynb
index 105d0ba..6b822a6 100644
--- a/sorting-searching/insertion-sort.ipynb
+++ b/sorting-searching/insertion-sort.ipynb
@@ -51,7 +51,7 @@
     "\n",
     "Complexity:\n",
     "* Time: O(n^2) avarage, worst.  O(1) best if input is already sorted.\n",
-    "* Space: O(1)"
+    "* Space: O(1), stable"
    ]
   },
   {
diff --git a/sorting-searching/quick-sort.ipynb b/sorting-searching/quick-sort.ipynb
index b29c7d8..01c7007 100644
--- a/sorting-searching/quick-sort.ipynb
+++ b/sorting-searching/quick-sort.ipynb
@@ -54,7 +54,7 @@
     "\n",
     "Complexity:\n",
     "* Time: O(n log(n)) average, best, O(n^2) worst\n",
-    "* Space: O(n), n extra space, n recursion depth"
+    "* Space: O(n), n extra space, n recursion depth, generally not stable"
    ]
   },
   {
diff --git a/sorting-searching/selection-sort.ipynb b/sorting-searching/selection-sort.ipynb
index 0982b92..2099aeb 100644
--- a/sorting-searching/selection-sort.ipynb
+++ b/sorting-searching/selection-sort.ipynb
@@ -51,7 +51,7 @@
     "\n",
     "Complexity:\n",
     "* Time: O(n^2) average, worst, best\n",
-    "* Space: O(1) iterative, O(n) recursive (unless tail-call elimination is available, then O(1))"
+    "* Space: O(1) iterative, O(n) recursive (unless tail-call elimination is available, then O(1)), generally not stable"
    ]
   },
   {