diff --git a/src/data_integration_lib.py b/src/data_integration_lib.py
index 8bd25b8..abfe397 100644
--- a/src/data_integration_lib.py
+++ b/src/data_integration_lib.py
@@ -18,7 +18,7 @@ def integrate_data_sources(yaml_config_file_path, log_dir='logs/'):
         log_dir (str): Directory to save the log file.
 
     Returns:
-        str: Path to the created HDF5 file.
+        str: Path (or list of Paths) to the created HDF5 file(s).
     """
 
     date = utils.created_at()
@@ -63,10 +63,12 @@ def integrate_data_sources(yaml_config_file_path, log_dir='logs/'):
             print(tmp)
 
         if 'experimental_step' in config_dict['integration_mode']: 
+            output_filename_path = []
             for datetime_step in datetime_augment_dict.keys():
                 date_str = datetime_step.strftime('%Y-%m-%d')
                 select_file_keywords = datetime_augment_dict[datetime_step]
-                output_filename_path = create_hdf5_file(date_str, select_file_keywords) 
+                dt_step_output_filename_path= create_hdf5_file(date_str, select_file_keywords) 
+                output_filename_path.append(dt_step_output_filename_path)
                 
         elif 'collection' in config_dict['integration_mode']:
             select_file_keywords = []