diff --git a/doerg/src/net/deertopia/doerg/element.clj b/doerg/src/net/deertopia/doerg/element.clj
index 404651a..ab85af3 100644
--- a/doerg/src/net/deertopia/doerg/element.clj
+++ b/doerg/src/net/deertopia/doerg/element.clj
@@ -209,5 +209,35 @@
                              rest)]
     (assoc node :children new-children)))
 
+(defn- neighbourly-mapcat [coll f]
+  (let [rest-coll (rest coll)]
+    (map f
+         coll
+         rest-coll
+         (concat (rest rest-coll) [nil]))))
+
+(comment
+  (-> [1 2 3 4]
+      (neighbourly-mapcat prn) )
+  (def doc (read-string (slurp some-org-file)))
+
+  (let [r (atom [])
+        blah
+        (sp/transform
+         [postorder-walker
+          (sp/must :children)
+          (sp/collect-one sp/VAL)
+          sp/INDEXED-VALS
+          #_
+          #(of-type? (second %) "latex-environment")
+          #_
+          sp/ALL
+          #_
+          sp/INDEXED-VALS]
+         (fn [siblings x]
+           x)
+         doc)]
+    @r))
+
 (defn gather-latex-paragraphs [node]
-  )
+  ())