diff --git a/oaipmh-core/pom.xml b/oaipmh-core/pom.xml
index 774aa24ba36c5e9769443613840dc62eb4567874..b2712da3b3431369fc216521d038108e3d1ef563 100644
--- a/oaipmh-core/pom.xml
+++ b/oaipmh-core/pom.xml
@@ -74,29 +74,29 @@
 			<artifactId>slf4j-api</artifactId>
 			<version>${slf4j.version}</version>
 		</dependency>
-<!-- 		<dependency> -->
-<!-- 			<groupId>org.slf4j</groupId> -->
-<!-- 			<artifactId>jcl-over-slf4j</artifactId> -->
-<!-- 			<version>${slf4j.version}</version> -->
-<!-- 			<scope>runtime</scope> -->
-<!-- 		</dependency> -->
-<!-- 		<dependency> -->
-<!-- 			<groupId>org.slf4j</groupId> -->
-<!-- 			<artifactId>slf4j-log4j12</artifactId> -->
-<!-- 			<version>${slf4j.version}</version> -->
-<!-- 			<scope>runtime</scope> -->
-<!-- 		</dependency> -->
-<!-- 		<dependency> -->
-<!-- 			<groupId>log4j</groupId> -->
-<!-- 			<artifactId>log4j</artifactId> -->
-<!-- 			<version>1.2.14</version> -->
-<!-- 		</dependency> -->
-		<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-core -->
-		<dependency>
-			<groupId>org.apache.logging.log4j</groupId>
-			<artifactId>log4j-core</artifactId>
-			<version>2.14.1</version>
+		<!-- <dependency> -->
+		<!-- <groupId>org.slf4j</groupId> -->
+		<!-- <artifactId>jcl-over-slf4j</artifactId> -->
+		<!-- <version>${slf4j.version}</version> -->
+		<!-- <scope>runtime</scope> -->
+		<!-- </dependency> -->
+		<!-- <dependency> -->
+		<!-- <groupId>org.slf4j</groupId> -->
+		<!-- <artifactId>slf4j-log4j12</artifactId> -->
+		<!-- <version>${slf4j.version}</version> -->
+		<!-- <scope>runtime</scope> -->
+		<!-- </dependency> -->
+		<dependency>
+			<groupId>log4j</groupId>
+			<artifactId>log4j</artifactId>
+			<version>1.2.14</version>
 		</dependency>
+		<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-core -->
+		<!-- <dependency> -->
+		<!-- <groupId>org.apache.logging.log4j</groupId> -->
+		<!-- <artifactId>log4j-core</artifactId> -->
+		<!-- <version>2.14.1</version> -->
+		<!-- </dependency> -->
 		<dependency>
 			<groupId>org.classicmayan.tools</groupId>
 			<artifactId>metsModsMapping</artifactId>
diff --git a/oaipmh-core/src/main/java/info/textgrid/middleware/IdentifierListDelivererDC.java b/oaipmh-core/src/main/java/info/textgrid/middleware/IdentifierListDelivererDC.java
index c66630c815a8d36fb842675c233d6a1b8af1e293..34f7d1bb6335715bef0d7a39315f7647e38b7c8f 100644
--- a/oaipmh-core/src/main/java/info/textgrid/middleware/IdentifierListDelivererDC.java
+++ b/oaipmh-core/src/main/java/info/textgrid/middleware/IdentifierListDelivererDC.java
@@ -37,7 +37,7 @@ import info.textgrid.middleware.oaipmh.ResumptionTokenType;
 
 public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
 
-  private Log log = LogFactory.getLog("info.textgrid.middleware");
+  private static Log logger = LogFactory.getLog(IdentifierListDelivererDC.class);
 
   private static final int lifeTimeResToken = 100;
   private static final String DH_ES_DIVIDER_CHAR = ".";
@@ -167,12 +167,12 @@ public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
     long size = listFurtherValues.getHits().totalHits;
     setResultSize(size);
 
-    log.info(" ## hits --> " + size);
+    logger.info(" ## hits --> " + size);
 
     for (SearchHit hit : listFurtherValues.getHits().getHits()) {
       i++;
 
-      this.log.info(" ## hit --> " + hit.getId());
+      this.logger.info(" ## hit --> " + hit.getId());
 
       // Handle TextGrid.
       if (this.textgrid) {
@@ -181,9 +181,9 @@ public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
         try {
           datestamp = OAIPMHUtilities.convertDateFormat(datestamp).toXMLFormat();
         } catch (ParseException e) {
-          this.log.error(e.getMessage());
+          this.logger.error(e.getMessage());
         } catch (DatatypeConfigurationException e) {
-          this.log.error(e.getMessage());
+          this.logger.error(e.getMessage());
         }
         String identifier = hit.getSourceAsMap().get(this.identifierField).toString();
         lit = setListIdentifierHeader(datestamp, identifier, lit, set);
@@ -192,7 +192,7 @@ public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
       // Handle DARIAH.
       else if (this.dariah) {
 
-        this.log.info(" ## dateOfObjectCreation --> " + this.dateOfObjectCreation);
+        this.logger.info(" ## dateOfObjectCreation --> " + this.dateOfObjectCreation);
 
         JSONObject json = new JSONObject(hit.getSourceAsMap());
 
@@ -231,17 +231,17 @@ public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
         // Convert datestamp.
         try {
 
-          this.log.info(" ## datestamp --> " + this.datestamp);
+          this.logger.info(" ## datestamp --> " + this.datestamp);
 
           this.datestamp = OAIPMHUtilities.convertDateFormat(this.datestamp).toXMLFormat();
 
-          this.log.info(" ## datestamp converted --> " + this.datestamp);
+          this.logger.info(" ## datestamp converted --> " + this.datestamp);
 
         } catch (ParseException e) {
-          this.log.error(e.getMessage());
+          this.logger.error(e.getMessage());
           // FIXME Go to ERROR state!
         } catch (DatatypeConfigurationException e) {
-          this.log.error(e.getMessage());
+          this.logger.error(e.getMessage());
           // FIXME Go to ERROR state!
         }
 
@@ -278,7 +278,7 @@ public class IdentifierListDelivererDC extends IdentifierListDelivererAbstract {
           identifier = hit.getSourceAsMap().get(this.identifierField).toString();
         }
 
-        this.log.info(" ## identifier --> " + identifier);
+        this.logger.info(" ## identifier --> " + identifier);
 
         lit = setListIdentifierHeader(this.datestamp, identifier, lit, set);
       }
diff --git a/oaipmh-core/src/main/java/info/textgrid/middleware/OAIPMHUtilities.java b/oaipmh-core/src/main/java/info/textgrid/middleware/OAIPMHUtilities.java
index 6a77e7848b4ab402ceae46eee75df151eed6234f..0b402b66b88f6cef48c4f26df9087b4d60f3e8bb 100644
--- a/oaipmh-core/src/main/java/info/textgrid/middleware/OAIPMHUtilities.java
+++ b/oaipmh-core/src/main/java/info/textgrid/middleware/OAIPMHUtilities.java
@@ -29,6 +29,7 @@ import javax.xml.stream.XMLStreamConstants;
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamReader;
 import org.apache.commons.io.IOUtils;
+import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.action.get.GetResponse;
@@ -73,6 +74,8 @@ import info.textgrid.middleware.common.TextGridMimetypes;
  */
 public class OAIPMHUtilities {
 
+  private static Log logger = LogFactory.getLog(OAIPMHUtilities.class);
+
   // **
   // FINALS
   // **
@@ -112,11 +115,7 @@ public class OAIPMHUtilities {
 
   protected static Map<String, Integer> cursorCollector = new Hashtable<String, Integer>();
 
-  // **
-  // STATICS
-  // **
-
-  private static org.apache.commons.logging.Log log = LogFactory.getLog(OAIPMHImpl.class);
+  // private static org.apache.commons.logging.Log log = LogFactory.getLog(OAIPMHImpl.class);
 
   /**
    * @param verb
@@ -328,7 +327,7 @@ public class OAIPMHUtilities {
       final String resumptionToken, Map<String, Integer> cursorCollector, final String scrollID,
       final int searchResponseSize, final int i) {
 
-    log.info("Creating a ResumptionToken:\n " +
+    logger.debug("Creating a ResumptionToken:\n " +
         "CompleteListSize: " + completeListSize + "\n" +
         "ResumptionToken: " + resumptionToken + "\n" +
         "CursorCollector: " + cursorCollector + "\n" +
@@ -471,20 +470,20 @@ public class OAIPMHUtilities {
             return null;
           }
         } else if (fieldPathForESIndex.length == 1) {
-        
+
           fieldResulsts.add(resultFromGetRequestInES.get(fieldPathForESIndex[i]).toString());
         } else {
           String res = singlePath.get(fieldPathForESIndex[i]).toString();
-          if(res.startsWith("[")) {
-        	  JSONArray array = new JSONArray(res);
-        	  for(int j=0; j<array.length(); j++) {
-           		  String find = array.getString(j).toString();        		  
-        		  fieldResulsts.add(find);
-        	  }
-          }else {
-        	  fieldResulsts.add(singlePath.get(fieldPathForESIndex[i]).toString());  
+          if (res.startsWith("[")) {
+            JSONArray array = new JSONArray(res);
+            for (int j = 0; j < array.length(); j++) {
+              String find = array.getString(j).toString();
+              fieldResulsts.add(find);
+            }
+          } else {
+            fieldResulsts.add(singlePath.get(fieldPathForESIndex[i]).toString());
           }
-          
+
         }
       }
     }
@@ -498,10 +497,11 @@ public class OAIPMHUtilities {
    * @return
    */
   public static String fieldLoader(JSONObject resultFromGetRequestInES, String field) {
-    
-	System.out.println("Inside fieldLoader for field: " + field);
+
     String fieldResulst = "";
 
+    System.out.println("Inside fieldLoader for field: " + field);
+
     String[] fieldPathForESIndex = field.split("\\.");
     JSONObject singlePath = resultFromGetRequestInES;
     for (int i = 0; i < fieldPathForESIndex.length; i++) {
diff --git a/oaipmh-core/src/main/java/info/textgrid/middleware/SetDeliverer.java b/oaipmh-core/src/main/java/info/textgrid/middleware/SetDeliverer.java
index a3d267f355fc4c96f0fd52653763772280babc4c..64f4017b64f6f8af636f163572cb981c14785538 100644
--- a/oaipmh-core/src/main/java/info/textgrid/middleware/SetDeliverer.java
+++ b/oaipmh-core/src/main/java/info/textgrid/middleware/SetDeliverer.java
@@ -27,7 +27,7 @@ import info.textgrid.middleware.oaipmh.SetType;
  */
 public class SetDeliverer {
 
-  private Log log = LogFactory.getLog("info.textgrid.middleware");
+  private static Log logger = LogFactory.getLog(SetDeliverer.class);
 
   private static final int DH_SIZE = 100000;
 
@@ -138,19 +138,19 @@ public class SetDeliverer {
 
     request.source(searchSourceBuilder);
 
-    this.log.info(" ## SetDeliverer() request --> " + request);
+    logger.info(" ## SetDeliverer() request --> " + request);
 
     // Get items with TG or DH request.
     SearchResponse getRecordListItems = null;
     try {
       getRecordListItems = OAI_ESClient.getEsClient().search(request, RequestOptions.DEFAULT);
 
-      this.log
+      logger
           .info(" ## SetDeliverer() list item count --> " + getRecordListItems.getHits().totalHits);
 
     } catch (IOException e) {
       // TODO Auto-generated catch block
-      this.log.error(e.getMessage());
+      logger.error(e.getMessage());
       e.printStackTrace();
     }
 
@@ -192,7 +192,7 @@ public class SetDeliverer {
 
           String name = entry.getKey();
 
-          this.log.info(" ## entry key --> " + entry.getKey());
+          logger.info(" ## entry key --> " + entry.getKey());
 
           if (name.equals(DH_COLLECTION_FILTER_NAME)) {
             Filter filterCollection =
@@ -203,16 +203,16 @@ public class SetDeliverer {
               // Divide ID and title.
               String combined = b.getKeyAsString();
 
-              this.log.info(" ## combined --> " + combined);
+              logger.info(" ## combined --> " + combined);
 
               int indexOf = combined.indexOf(DH_FIELD_DIVIDER);
               String id = combined.substring(0, indexOf);
 
-              this.log.info(" ## id --> " + id);
+              logger.info(" ## id --> " + id);
 
               String title = combined.substring(indexOf + 1);
 
-              this.log.info(" ## title --> " + title);
+              logger.info(" ## title --> " + title);
 
               // Set set.
               SetType newSet = new SetType();