diff --git a/src/main/java/org/hostsharing/hsadminng/service/dto/CustomerDTO.java b/src/main/java/org/hostsharing/hsadminng/service/dto/CustomerDTO.java
index 368e9038..de2a6ba3 100644
--- a/src/main/java/org/hostsharing/hsadminng/service/dto/CustomerDTO.java
+++ b/src/main/java/org/hostsharing/hsadminng/service/dto/CustomerDTO.java
@@ -2,7 +2,6 @@ package org.hostsharing.hsadminng.service.dto;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.core.TreeNode;
 import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.JsonDeserializer;
@@ -57,10 +56,6 @@ public class CustomerDTO implements Serializable {
     @AccessFor(init = Role.ADMIN, update = Role.ADMIN, read = Role.CONTRACTUAL_CONTACT)
     private String contractualAddress;
 
-    @Size(max = 80)
-    @AccessFor(init = Role.ADMIN, update = Role.CONTRACTUAL_CONTACT, read = Role.ANY_CUSTOMER_CONTACT)
-    private String contractualSalutation;
-
     @Size(max = 80)
     @AccessFor(init = Role.ADMIN, update = {Role.CONTRACTUAL_CONTACT, Role.FINANCIAL_CONTACT}, read = Role.CONTRACTUAL_CONTACT)
     private String billingSalutation;
@@ -182,10 +177,10 @@ public class CustomerDTO implements Serializable {
     }
 
     @JsonComponent
-    public static class CustomerJsonSerializer extends JsonSerializer<CustomerDTO> {
+    public static class JsonSerializerWithAccessFilter extends JsonSerializer<Object> {
 
         @Override
-        public void serialize(CustomerDTO dto, JsonGenerator jsonGenerator,
+        public void serialize(Object dto, JsonGenerator jsonGenerator,
                               SerializerProvider serializerProvider) throws IOException {
 
             jsonGenerator.writeStartObject();
@@ -196,7 +191,7 @@ public class CustomerDTO implements Serializable {
             jsonGenerator.writeEndObject();
         }
 
-        private void toJSon(CustomerDTO dto, JsonGenerator jsonGenerator, Field prop) throws IOException {
+        private void toJSon(Object dto, JsonGenerator jsonGenerator, Field prop) throws IOException {
             if (getLoginUserRole().isAllowedToRead(prop)) {
                 final String fieldName = prop.getName();
                 if (Integer.class.isAssignableFrom(prop.getType()) || int.class.isAssignableFrom(prop.getType())) {
@@ -211,7 +206,7 @@ public class CustomerDTO implements Serializable {
             }
         }
 
-        private Object get(CustomerDTO dto, Field field) {
+        private Object get(Object dto, Field field) {
             try {
                 field.setAccessible(true);
                 return field.get(dto);
@@ -239,20 +234,20 @@ public class CustomerDTO implements Serializable {
 
         @Override
         public CustomerDTO deserialize(JsonParser jsonParser,
-                                       DeserializationContext deserializationContext) throws IOException,
-            JsonProcessingException {
+                                       DeserializationContext deserializationContext) throws IOException {
 
             TreeNode treeNode = jsonParser.getCodec().readTree(jsonParser);
 
             CustomerDTO dto = new CustomerDTO();
             dto.setId(((IntNode) treeNode.get("id")).asLong());
-            dto.setNumber(((IntNode) treeNode.get("number")).asInt());
+            dto.setReference(((IntNode) treeNode.get("reference")).asInt());
             dto.setPrefix(((TextNode) treeNode.get("prefix")).asText());
             dto.setName(((TextNode) treeNode.get("name")).asText());
             dto.setContractualAddress(((TextNode) treeNode.get("contractualAddress")).asText());
             dto.setContractualSalutation(((TextNode) treeNode.get("contractualSalutation")).asText());
             dto.setBillingAddress(((TextNode) treeNode.get("billingAddress")).asText());
             dto.setBillingSalutation(((TextNode) treeNode.get("billingSalutation")).asText());
+            dto.setRemark(((TextNode) treeNode.get("remark")).asText());
 
             return dto;
         }
diff --git a/src/test/java/org/hostsharing/hsadminng/service/dto/CustomerDTOUnitTest.java b/src/test/java/org/hostsharing/hsadminng/service/dto/CustomerDTOUnitTest.java
index b6be38c9..1ad1cc5d 100644
--- a/src/test/java/org/hostsharing/hsadminng/service/dto/CustomerDTOUnitTest.java
+++ b/src/test/java/org/hostsharing/hsadminng/service/dto/CustomerDTOUnitTest.java
@@ -41,6 +41,7 @@ public class CustomerDTOUnitTest {
         given.setContractualSalutation(null);
         given.setBillingAddress(null);
         given.setBillingSalutation(null);
+        given.setRemark(null);
         assertEquals(createExpectedJSon(given), actual);
     }
 
@@ -55,13 +56,13 @@ public class CustomerDTOUnitTest {
         String actual = objectMapper.writeValueAsString(given);
 
         // then
-        assertEquals(createExpectedJSon(given), actual);
+        assertThat(actual).isEqualTo(createExpectedJSon(given));
     }
 
     @Test
     public void testDeserializeAsContractualCustomerContact() throws IOException {
         // given
-        String json = "{\"id\":1234,\"number\":10001,\"prefix\":\"abc\",\"name\":\"Mein Name\",\"contractualAddress\":\"Eine Adresse\",\"contractualSalutation\":\"Hallo\",\"billingAddress\":\"Noch eine Adresse\",\"billingSalutation\":\"Moin\"}";
+        String json = "{\"id\":1234,\"reference\":10001,\"prefix\":\"abc\",\"name\":\"Mein Name\",\"contractualAddress\":\"Eine Adresse\",\"contractualSalutation\":\"Hallo\",\"billingAddress\":\"Noch eine Adresse\",\"billingSalutation\":\"Moin\",\"remark\":\"Eine Bemerkung\"}";
         givenLoginUserWithRole("CONTRACTUAL_CONTACT");
 
         // when
@@ -70,26 +71,28 @@ public class CustomerDTOUnitTest {
         // then
         CustomerDTO expected = new CustomerDTO();
         expected.setId(1234L);
-        expected.setNumber(10001);
+        expected.setReference(10001);
         expected.setPrefix("abc");
         expected.setName("Mein Name");
         expected.setContractualAddress(null); // not allowed
         expected.setContractualSalutation("Hallo");
         expected.setBillingAddress("Noch eine Adresse");
         expected.setBillingSalutation("Moin");
+        expected.setRemark("Eine Bemerkung");
         assertEquals(actual, expected);
     }
 
     private String createExpectedJSon(CustomerDTO dto) {
         String json = // the fields in alphanumeric order:
             toJSonFieldDefinitionIfPresent("id", dto.getId()) +
-                toJSonFieldDefinitionIfPresent("number", dto.getNumber()) +
+                toJSonFieldDefinitionIfPresent("reference", dto.getReference()) +
                 toJSonFieldDefinitionIfPresent("prefix", dto.getPrefix()) +
                 toJSonFieldDefinitionIfPresent("name", dto.getName()) +
-                toJSonFieldDefinitionIfPresent("contractualAddress", dto.getContractualAddress()) +
                 toJSonFieldDefinitionIfPresent("contractualSalutation", dto.getContractualSalutation()) +
+                toJSonFieldDefinitionIfPresent("contractualAddress", dto.getContractualAddress()) +
+                toJSonFieldDefinitionIfPresent("billingSalutation", dto.getBillingSalutation()) +
                 toJSonFieldDefinitionIfPresent("billingAddress", dto.getBillingAddress()) +
-                toJSonFieldDefinitionIfPresent("billingSalutation", dto.getBillingSalutation());
+                toJSonFieldDefinitionIfPresent("remark", dto.getRemark()) ;
         return "{" + json.substring(0, json.length() - 1) + "}";
     }
 
@@ -108,14 +111,14 @@ public class CustomerDTOUnitTest {
     private CustomerDTO createSomeCustomerDTO() {
         CustomerDTO given = new CustomerDTO();
         given.setId(1234L);
-        given.setNumber(10001);
+        given.setReference(10001);
         given.setPrefix("abc");
         given.setName("Mein Name");
         given.setContractualAddress("Eine Adresse");
         given.setContractualSalutation("Hallo");
         given.setBillingAddress("Noch eine Adresse");
         given.setBillingSalutation("Moin");
-        givenLoginUserWithRole("admin");
+        given.setRemark("Eine Bemerkung");
         return given;
     }