diff --git a/README.md b/README.md
index 1b6623e..4774cfb 100644
--- a/README.md
+++ b/README.md
@@ -70,7 +70,7 @@ Plugin versions are available for (at least) all minor versions of Elasticsearch
 The first 3 digits of plugin version is Elasticsearch versioning. The last digit is used for plugin versioning under an elasticsearch version.
 
 To install it, launch this command in Elasticsearch directory replacing the url by the correct link for your Elasticsearch version (see table)
-`./bin/elasticsearch-plugin install https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.4.1.0/geopoint-clustering-aggregation-6.4.1.0.zip`
+`./bin/elasticsearch-plugin install https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.4.2.0/geopoint-clustering-aggregation-6.4.2.0.zip`
 
 | elasticsearch version | plugin version | plugin url |
 | --------------------- | -------------- | ---------- |
@@ -78,5 +78,4 @@ To install it, launch this command in Elasticsearch directory replacing the url
 | 6.1.4 | 6.1.4.0 | https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.1.4.0/geopoint-clustering-aggregation-6.1.4.0.zip|
 | 6.2.4 | 6.2.4.0 | https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.2.4.0/geopoint-clustering-aggregation-6.2.4.0.zip|
 | 6.3.2 | 6.3.2.0 | https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.3.2.0/geopoint-clustering-aggregation-6.3.2.0.zip|
-| 6.4.1 | 6.4.1.0 | https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.4.1.0/geopoint-clustering-aggregation-6.4.1.0.zip|
-  
\ No newline at end of file
+| 6.4.2 | 6.4.2.0 | https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v6.4.2.0/geopoint-clustering-aggregation-6.4.2.0.zip|
diff --git a/gradle.properties b/gradle.properties
index 8ef9331..3ad9d7d 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,2 +1,2 @@
-es_version = 6.4.1
-plugin_version = 6.4.1.0
+es_version = 6.4.2
+plugin_version = 6.4.2.0
diff --git a/src/main/java/com/opendatasoft/elasticsearch/search/aggregations/bucket/geopointclustering/GeoPointClusteringAggregator.java b/src/main/java/com/opendatasoft/elasticsearch/search/aggregations/bucket/geopointclustering/GeoPointClusteringAggregator.java
index 693b136..5b68755 100644
--- a/src/main/java/com/opendatasoft/elasticsearch/search/aggregations/bucket/geopointclustering/GeoPointClusteringAggregator.java
+++ b/src/main/java/com/opendatasoft/elasticsearch/search/aggregations/bucket/geopointclustering/GeoPointClusteringAggregator.java
@@ -4,7 +4,6 @@
 import org.elasticsearch.common.geo.GeoHashUtils;
 import org.elasticsearch.common.geo.GeoPoint;
 import org.elasticsearch.common.lease.Releasables;
-import org.elasticsearch.common.util.LongArray;
 import org.elasticsearch.common.util.LongHash;
 import org.elasticsearch.common.util.ObjectArray;
 import org.elasticsearch.index.fielddata.MultiGeoPointValues;