diff --git a/src/main/java/eu/simstadt/regionchooser/RegionExtractor.java b/src/main/java/eu/simstadt/regionchooser/RegionExtractor.java
index 316d378bd2c5c92365adeebd7f5d539122746a65..a13894cc1e9d6d0a09b5b596c782ac77fb875a6f 100644
--- a/src/main/java/eu/simstadt/regionchooser/RegionExtractor.java
+++ b/src/main/java/eu/simstadt/regionchooser/RegionExtractor.java
@@ -32,13 +32,13 @@
 	 * same coordinate system as the CityGML), it iterates over each Building and checks if the building is inside the
 	 * geometry. It only works with CityGML files smaller than 2GB. It uses VTD-XML parser instead of a whole
 	 * Simstadt/Citydoctor/Citygml model.
-	 * 
+	 *
 	 * @param wktPolygon
 	 * @param srsName
 	 * @param output
 	 * @param citygmlPaths
-	 * 
-	 * 
+	 *
+	 *
 	 * @writes the extracted Citygml, including header, buildings and footer to output
 	 * @return counts of found building.
 	 * @throws ParseException
@@ -88,6 +88,7 @@ static int selectRegionDirectlyFromCityGML(String wktPolygon, String srsName, Wr
 		}
 
 		LOGGER.info("Buildings found in selected region " + foundBuildingsCount);
+		//NOTE: This could be a problem if header starts with <core:CityModel> and footer ends with </CityModel>
 		sb.append(citygml.getFooter());
 		return foundBuildingsCount;
 	}
@@ -99,7 +100,7 @@ static int selectRegionDirectlyFromCityGML(String wktPolygon, String srsName, Wr
 	 * from the extracting polygon. The real envelope might be even smaller, but it could only be known at the end of the
 	 * parsing, after having analyzed every building. The envelope should be written in the header. If present, min and
 	 * max values for Z are kept.
-	 * 
+	 *
 	 * @param header
 	 * @param envelope
 	 * @param srsName