diff --git a/include/boost/geometry/extensions/index/algorithms/maxdist.hpp b/include/boost/geometry/extensions/index/algorithms/maxdist.hpp
index 1aa7a9b94..b207d271d 100644
--- a/include/boost/geometry/extensions/index/algorithms/maxdist.hpp
+++ b/include/boost/geometry/extensions/index/algorithms/maxdist.hpp
@@ -55,11 +55,11 @@ template <typename Point, typename Indexable>
 typename geometry::default_distance_result<Point, Indexable>::type
 maxdist(Point const& pt, Indexable const& i)
 {
-    return sum_for_indexable<
+    return detail::sum_for_indexable<
         Point,
         Indexable,
         typename index::traits::tag<Indexable>::type,
-        maxdist_tag,
+        detail::maxdist_tag,
         index::traits::dimension<Indexable>::value
     >::apply(pt, i);
 }
diff --git a/include/boost/geometry/extensions/index/rtree/visitors/nearest.hpp b/include/boost/geometry/extensions/index/rtree/visitors/nearest.hpp
index c9fb77d39..da950e7f4 100644
--- a/include/boost/geometry/extensions/index/rtree/visitors/nearest.hpp
+++ b/include/boost/geometry/extensions/index/rtree/visitors/nearest.hpp
@@ -12,6 +12,7 @@
 
 #include <boost/geometry/extensions/index/algorithms/mindist.hpp>
 #include <boost/geometry/extensions/index/algorithms/minmaxdist.hpp>
+#include <boost/geometry/extensions/index/algorithms/maxdist.hpp>
 
 #include <boost/geometry/extensions/index/rtree/node/node.hpp>
 
@@ -19,6 +20,10 @@ namespace boost { namespace geometry { namespace index {
 
 namespace detail { namespace rtree { namespace visitors {
 
+// TODO: awulkiew - maby it's a good idea to check if curr_mindist < comp_mindist and then check predicates
+// in store() or break store to 2 functions e.g. should_store() and store()
+// - well not with this algorithm of storing k-th neighbor
+
 template <typename Value, typename Translator, typename Point>
 struct nearest_one
 {
@@ -85,6 +90,7 @@ public:
         // TODO: awulkiew - test other methods:
         // heap, manual inserting
         // don't sort if size < k ?
+        // check the furthest distance at the first place, before push_back()
     }
 
     inline bool is_mindist_valid() const