diff --git a/summarizer/cluster_features.py b/summarizer/cluster_features.py
index 3759458..a7cf3e8 100644
--- a/summarizer/cluster_features.py
+++ b/summarizer/cluster_features.py
@@ -162,4 +162,4 @@ def __call__(self, ratio: float = 0.1, num_sentences: int = None) -> List[int]:
         :param num_sentences: Number of sentences. Overrides ratio.
         :return: Sentences index that qualify for summary.
         """
-        return self.cluster(ratio)
+        return self.cluster(ratio, num_sentences)