diff --git a/src/User/AuthClient/Facebook.php b/src/User/AuthClient/Facebook.php
index e2a3ce1..b910539 100644
--- a/src/User/AuthClient/Facebook.php
+++ b/src/User/AuthClient/Facebook.php
@@ -31,6 +31,7 @@ class Facebook extends BaseFacebook implements AuthClientInterface
      */
     public function getUsername()
     {
-        return null;
+        /* returns the e-mail as it corresponds with the username */
+        return $this->getEmail();
     }
 }
diff --git a/src/User/AuthClient/Google.php b/src/User/AuthClient/Google.php
index 871dabc..4f04e01 100644
--- a/src/User/AuthClient/Google.php
+++ b/src/User/AuthClient/Google.php
@@ -31,6 +31,7 @@ class Google extends BaseGoogle implements AuthClientInterface
      */
     public function getUsername()
     {
-        return null;
+        /* returns the e-mail as it corresponds with the username */
+        return $this->getEmail();
     }
 }
diff --git a/src/User/AuthClient/LinkedIn.php b/src/User/AuthClient/LinkedIn.php
index 9528760..b99aa5b 100644
--- a/src/User/AuthClient/LinkedIn.php
+++ b/src/User/AuthClient/LinkedIn.php
@@ -31,6 +31,7 @@ class LinkedIn extends BaseLinkedIn implements AuthClientInterface
      */
     public function getUsername()
     {
-        return null;
+        /* returns the e-mail as it corresponds with the username */
+        return $this->getEmail();
     }
 }