diff --git a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/json/input/TimeSeriesBean.java b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/json/input/TimeSeriesBean.java
index b210c46..e548471 100644
--- a/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/json/input/TimeSeriesBean.java
+++ b/src/main/java/org/gcube/data_catalogue/grsf_publish_ws/json/input/TimeSeriesBean.java
@@ -64,7 +64,8 @@ public class TimeSeriesBean<T, T1> implements Comparable<TimeSeriesBean<T, T1>>{
 	@Override
 	public String toString() {
 
-		if(this.unit != null && !this.unit.getClass().equals(Void.class)) // e.g., catches and landings
+		if(this.unit != null && !this.unit.getClass().equals(Void.class)
+				&& !this.unit.toString().isEmpty()) // e.g., catches and landings
 			return year + "-" + value + "-" + unit;
 		else
 			return year + "-" + value;