diff --git a/.gitignore b/.gitignore
index 1bfe614..1bc7782 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,4 +7,5 @@ packages
 .packages
 *.iml
 .dart_tool
-/test/smtpserver.json
\ No newline at end of file
+/test/smtpserver.json
+.DS_Store
\ No newline at end of file
diff --git a/lib/src/entities/address.dart b/lib/src/entities/address.dart
index d716697..11b67a1 100644
--- a/lib/src/entities/address.dart
+++ b/lib/src/entities/address.dart
@@ -3,4 +3,11 @@ class Address {
   String mailAddress;
 
   Address([this.mailAddress, this.name]);
+
+  @override
+  String toString() {
+    var fromName = name ?? '';
+    // ToDo base64 fromName (add _IRMetaInformation as argument)
+    return '$fromName <$mailAddress>';
+  }
 }
diff --git a/lib/src/entities/message.dart b/lib/src/entities/message.dart
index 3fc399d..6314792 100644
--- a/lib/src/entities/message.dart
+++ b/lib/src/entities/message.dart
@@ -71,6 +71,6 @@ class Message {
   String html;
   List<Attachment> attachments = [];
 
-  Iterable<Address> _asAddresses(Iterable<dynamic> as) =>
-      (as ?? []).map((a) => a is String ? Address(a) : a as Address);
+  static Iterable<Address> _asAddresses(Iterable<dynamic> adrs) =>
+      adrs == null ? []: adrs.map((a) => a is String ? Address(a) : a as Address);
 }
diff --git a/lib/src/smtp/internal_representation/ir_header.dart b/lib/src/smtp/internal_representation/ir_header.dart
index aaa700a..ecd7a46 100644
--- a/lib/src/smtp/internal_representation/ir_header.dart
+++ b/lib/src/smtp/internal_representation/ir_header.dart
@@ -62,14 +62,8 @@ class _IRHeaderText extends _IRHeader {
   }
 }
 
-Iterable<String> _addressToString(Iterable<Address> addresses) {
-  if (addresses == null) return [];
-  return addresses.map((a) {
-    var fromName = a.name ?? '';
-    // ToDo base64 fromName (add _IRMetaInformation as argument)
-    return '$fromName <${a.mailAddress}>';
-  });
-}
+Iterable<String> _addressToString(Iterable<Address> addresses)
+=> assress == null ? []: addresses.map((a) => a.toString());
 
 class _IRHeaderAddress extends _IRHeader {
   Address _address;