diff --git a/validator/src/test/java/org/mustangproject/validator/ZUGFeRDValidatorTest.java b/validator/src/test/java/org/mustangproject/validator/ZUGFeRDValidatorTest.java
index 4a4638b6..3293ebf3 100644
--- a/validator/src/test/java/org/mustangproject/validator/ZUGFeRDValidatorTest.java
+++ b/validator/src/test/java/org/mustangproject/validator/ZUGFeRDValidatorTest.java
@@ -2,6 +2,15 @@ package org.mustangproject.validator;
 
 import java.io.ByteArrayInputStream;
 import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import org.xmlunit.builder.Input;
+import org.xmlunit.xpath.JAXPXPathEngine;
+import org.xmlunit.xpath.XPathEngine;
 
 import static org.xmlunit.assertj.XmlAssert.assertThat;