diff --git a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/DocumentationBuilder.groovy b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/DocumentationBuilder.groovy
index aa2830b20..242a28fe9 100644
--- a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/DocumentationBuilder.groovy
+++ b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/DocumentationBuilder.groovy
@@ -17,6 +17,12 @@
  */
 package org.dkpro.core.doc;
 
+import static groovy.io.FileType.FILES;
+import org.dkpro.meta.core.MetadataAggregator
+import org.dkpro.meta.core.model.MetadataModel
+import org.dkpro.meta.core.maven.ContextHolder
+import org.yaml.snakeyaml.Yaml
+
 class DocumentationBuilder {
     public void run() {
         File dkproCorePath = new File(ContextHolder.basedir, '..');
diff --git a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/PomSanityCheck.groovy b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/PomSanityCheck.groovy
index de76fbf4d..d8f927b26 100644
--- a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/PomSanityCheck.groovy
+++ b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/PomSanityCheck.groovy
@@ -17,6 +17,10 @@
  */
 package org.dkpro.core.doc
 
+import static groovy.io.FileType.FILES;
+import org.dkpro.meta.core.maven.ContextHolder
+import groovy.xml.XmlParser
+
 class PomSanityCheck {
     public void run() {
         ContextHolder.log.info("Running POM sanity check ${ContextHolder.basedir}...")
diff --git a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/Util.groovy b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/Util.groovy
index bcc05140a..471a53185 100644
--- a/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/Util.groovy
+++ b/dkpro-core-doc/src/main/groovy/org/dkpro/core/doc/Util.groovy
@@ -17,6 +17,8 @@
  */
 package org.dkpro.core.doc
 
+import java.text.BreakIterator
+
 class Util {
     static def editOnGithub(url)
     {