diff --git a/similarity_search/src/method/hnsw.cc b/similarity_search/src/method/hnsw.cc
index a9bd09d..6b4d778 100644
--- a/similarity_search/src/method/hnsw.cc
+++ b/similarity_search/src/method/hnsw.cc
@@ -869,7 +869,7 @@ namespace similarity {
 
         ElList_.resize(totalElementsStored_);
         for (unsigned id = 0; id < totalElementsStored_; ++id) {
-            ElList_[id] = new HnswNode(data_[id], id);
+            ElList_[id] = new HnswNode(this->data_[id], id);
         }
 
         enterpoint_ = ElList_[enterpointId_];
@@ -926,7 +926,7 @@ namespace similarity {
 
         ElList_.resize(totalElementsStored_);
         for (unsigned id = 0; id < totalElementsStored_; ++id) {
-            ElList_[id] = new HnswNode(data_[id], id);
+            ElList_[id] = new HnswNode(this->data_[id], id);
         }
 
         enterpoint_ = ElList_[enterpointId_];