diff --git a/dbnomics/__init__.py b/dbnomics/__init__.py
index d105bfa170add4d33644b20a696cc65bb03c117e..8b6969b4a22c559acbe30db7a98b587504b08954 100644
--- a/dbnomics/__init__.py
+++ b/dbnomics/__init__.py
@@ -211,7 +211,8 @@ def fetch_series_by_api_link(api_link, max_nb_series=None,
         dataset_dimensions = datasets_dimensions[complete_dataset_code]
         for dimension_code, dimension_label in dataset_dimensions['dimensions_labels'].items():
             dimension_value_code = series_dims_by_dataset_code[complete_dataset_code][dimension_code]
-            flat_series[dimension_label] = dataset_dimensions['dimensions_values_labels'][dimension_code][dimension_value_code]
+            flat_series[dimension_label] = dict(dataset_dimensions['dimensions_values_labels']
+                                                [dimension_code])[dimension_value_code]
         flat_series_list.append(flat_series)
 
     # Only applies if filters are used.