DOC: Mention bookbook

Author: mgeier

doc/links.ipynb

@@ -116,6 +116,18 @@
     "See https://github.com/spatialaudio/nbsphinx/pull/33 for some limitations."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "**bookbook**\n",
+    "\n",
+    "Uses `nbconvert` to create a sequence of HTML or\n",
+    "a concatenated LaTeX file from a sequence of notebooks.\n",
+    "\n",
+    "https://github.com/takluyver/bookbook"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -188,7 +200,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.7"
+   "version": "3.7.1"
   }
  },
  "nbformat": 4,