diff --git a/src/Utopia/Messaging/Adapter/Email/Sendgrid.php b/src/Utopia/Messaging/Adapter/Email/Sendgrid.php
index 2fef19f..10b26f1 100644
--- a/src/Utopia/Messaging/Adapter/Email/Sendgrid.php
+++ b/src/Utopia/Messaging/Adapter/Email/Sendgrid.php
@@ -39,6 +39,7 @@ public function getMaxMessagesPerRequest(): int
      */
     protected function process(EmailMessage $message): array
     {
+        // https://www.twilio.com/docs/sendgrid/for-developers/sending-email/personalizations#-Sending-Two-Different-Emails-to-Two-Different-Groups-of-Recipients
         $personalizations = \array_map(
             fn ($to) => [
                 'to' => [['email' => $to]],