diff --git a/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php b/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
index c20df73541..f4c932ebb2 100644
--- a/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
+++ b/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
@@ -30,7 +30,10 @@
 namespace Espo\Classes\FieldProcessing\Email;
 
 use Espo\Core\Name\Field;
+use Espo\Entities\User;
 use Espo\Modules\Crm\Entities\Call;
+use Espo\Modules\Crm\Entities\Contact;
+use Espo\Modules\Crm\Entities\Lead;
 use Espo\Modules\Crm\Entities\Meeting;
 use Espo\ORM\Entity;
 use Espo\ORM\EntityManager;
@@ -57,9 +60,9 @@ class IcsDataLoader implements Loader
 {
     /** @var array<string, string> */
     private $entityTypeLinkMap = [
-        'User' => 'users',
-        'Contact' => 'contacts',
-        'Lead' => 'leads',
+        User::ENTITY_TYPE => Meeting::LINK_USERS,
+        Contact::ENTITY_TYPE => Meeting::LINK_CONTACTS,
+        Lead::ENTITY_TYPE => Meeting::LINK_LEADS,
     ];
 
     public function __construct(private EntityManager $entityManager, private Log $log)
diff --git a/application/Espo/Modules/Crm/Business/Event/Invitations.php b/application/Espo/Modules/Crm/Business/Event/Invitations.php
index 5fb9593ed5..bcced8a031 100644
--- a/application/Espo/Modules/Crm/Business/Event/Invitations.php
+++ b/application/Espo/Modules/Crm/Business/Event/Invitations.php
@@ -291,7 +291,9 @@ class Invitations
         $attendees = [];
 
         /** @var iterable<User> $users */
-        $users = $this->entityManager->getRelation($entity, 'users')->find();
+        $users = $this->entityManager
+            ->getRelation($entity, Meeting::LINK_USERS)
+            ->find();
 
         foreach ($users as $it) {
             $address = $it->getEmailAddress();
@@ -303,7 +305,9 @@ class Invitations
         }
 
         /** @var iterable<Contact> $contacts */
-        $contacts = $this->entityManager->getRelation($entity, 'contacts')->find();
+        $contacts = $this->entityManager
+            ->getRelation($entity, Meeting::LINK_CONTACTS)
+            ->find();
 
         foreach ($contacts as $it) {
             $address = $it->getEmailAddress();
@@ -315,7 +319,9 @@ class Invitations
         }
 
         /** @var iterable<Lead> $leads */
-        $leads = $this->entityManager->getRelation($entity, 'leads')->find();
+        $leads = $this->entityManager
+            ->getRelation($entity, Meeting::LINK_LEADS)
+            ->find();
 
         foreach ($leads as $it) {
             $address = $it->getEmailAddress();
@@ -334,7 +340,9 @@ class Invitations
         $timeZone = $this->applicationConfig->getTimeZone();
 
         if ($invitee instanceof User) {
-            $preferences = $this->entityManager->getRepositoryByClass(Preferences::class)->getById($invitee->getId());
+            $preferences = $this->entityManager
+                ->getRepositoryByClass(Preferences::class)
+                ->getById($invitee->getId());
 
             if ($preferences && $preferences->getTimeZone()) {
                 $timeZone = $preferences->getTimeZone();
diff --git a/application/Espo/Modules/Crm/Classes/FieldProcessing/Call/PhoneNumberMapLoader.php b/application/Espo/Modules/Crm/Classes/FieldProcessing/Call/PhoneNumberMapLoader.php
index 3f3fec1fc4..873b3b88f2 100644
--- a/application/Espo/Modules/Crm/Classes/FieldProcessing/Call/PhoneNumberMapLoader.php
+++ b/application/Espo/Modules/Crm/Classes/FieldProcessing/Call/PhoneNumberMapLoader.php
@@ -30,6 +30,9 @@
 namespace Espo\Modules\Crm\Classes\FieldProcessing\Call;
 
 use Espo\Modules\Crm\Entities\Call;
+use Espo\Modules\Crm\Entities\Contact;
+use Espo\Modules\Crm\Entities\Lead;
+use Espo\Modules\Crm\Entities\Meeting;
 use Espo\ORM\Entity;
 use Espo\Core\ORM\Entity as CoreEntity;
 use Espo\Core\FieldProcessing\Loader;
@@ -55,16 +58,16 @@ class PhoneNumberMapLoader implements Loader
 
         assert($entity instanceof CoreEntity);
 
-        $contactIdList = $entity->getLinkMultipleIdList('contacts');
+        $contactIdList = $entity->getLinkMultipleIdList(Meeting::LINK_CONTACTS);
 
         if (count($contactIdList)) {
-            $this->populate($map, 'Contact', $contactIdList);
+            $this->populate($map, Contact::ENTITY_TYPE, $contactIdList);
         }
 
-        $leadIdList = $entity->getLinkMultipleIdList('leads');
+        $leadIdList = $entity->getLinkMultipleIdList(Meeting::LINK_LEADS);
 
         if (count($leadIdList)) {
-            $this->populate($map, 'Lead', $leadIdList);
+            $this->populate($map, Lead::ENTITY_TYPE, $leadIdList);
         }
 
         $entity->set('phoneNumbersMap', $map);
diff --git a/application/Espo/Modules/Crm/Entities/Call.php b/application/Espo/Modules/Crm/Entities/Call.php
index aa27d5f748..29b77d9125 100644
--- a/application/Espo/Modules/Crm/Entities/Call.php
+++ b/application/Espo/Modules/Crm/Entities/Call.php
@@ -131,34 +131,34 @@ class Call extends Entity
     public function getUsers(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('users');
+        return $this->getValueObject(Meeting::LINK_USERS);
     }
 
     public function getContacts(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('contacts');
+        return $this->getValueObject(Meeting::LINK_CONTACTS);
     }
 
     public function getLeads(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('leads');
+        return $this->getValueObject(Meeting::LINK_LEADS);
     }
 
     public function setUsers(LinkMultiple $users): self
     {
-        return $this->setValueObject('users', $users);
+        return $this->setValueObject(Meeting::LINK_USERS, $users);
     }
 
     public function setContacts(LinkMultiple $contacts): self
     {
-        return $this->setValueObject('contacts', $contacts);
+        return $this->setValueObject(Meeting::LINK_CONTACTS, $contacts);
     }
 
     public function setLeads(LinkMultiple $leads): self
     {
-        return $this->setValueObject('leads', $leads);
+        return $this->setValueObject(Meeting::LINK_LEADS, $leads);
     }
 
     public function setParent(Entity|LinkParent|null $parent): self
diff --git a/application/Espo/Modules/Crm/Entities/Meeting.php b/application/Espo/Modules/Crm/Entities/Meeting.php
index a2e6b68939..19dfdff04c 100644
--- a/application/Espo/Modules/Crm/Entities/Meeting.php
+++ b/application/Espo/Modules/Crm/Entities/Meeting.php
@@ -51,6 +51,10 @@ class Meeting extends Entity
     public const STATUS_HELD = 'Held';
     public const STATUS_NOT_HELD = 'Not Held';
 
+    public const LINK_USERS = 'users';
+    public const LINK_CONTACTS = 'contacts';
+    public const LINK_LEADS = 'leads';
+
     public function setName(?string $name): self
     {
         return $this->set(Field::NAME, $name);
@@ -136,34 +140,34 @@ class Meeting extends Entity
     public function getUsers(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('users');
+        return $this->getValueObject(self::LINK_USERS);
     }
 
     public function getContacts(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('contacts');
+        return $this->getValueObject(self::LINK_CONTACTS);
     }
 
     public function getLeads(): LinkMultiple
     {
         /** @var LinkMultiple */
-        return $this->getValueObject('leads');
+        return $this->getValueObject(self::LINK_LEADS);
     }
 
     public function setUsers(LinkMultiple $users): self
     {
-        return $this->setValueObject('users', $users);
+        return $this->setValueObject(self::LINK_USERS, $users);
     }
 
     public function setContacts(LinkMultiple $contacts): self
     {
-        return $this->setValueObject('contacts', $contacts);
+        return $this->setValueObject(self::LINK_CONTACTS, $contacts);
     }
 
     public function setLeads(LinkMultiple $leads): self
     {
-        return $this->setValueObject('leads', $leads);
+        return $this->setValueObject(self::LINK_LEADS, $leads);
     }
 
     public function setParent(Entity|LinkParent|null $parent): self
diff --git a/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php b/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
index 25cf0e6095..a05bc6e1aa 100644
--- a/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
+++ b/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
@@ -30,7 +30,6 @@
 namespace Espo\Modules\Crm\Tools\Meeting\Invitation;
 
 use Espo\Core\Binding\BindingContainerBuilder;
-use Espo\Core\Exceptions\Error;
 use Espo\Core\Exceptions\Forbidden;
 use Espo\Core\InjectableFactory;
 use Espo\Core\Mail\Exceptions\SendingError;
@@ -67,7 +66,6 @@ class Sender
      * @param Meeting|Call $entity
      * @param ?Invitee[] $targets
      * @return Entity[] Entities an invitation was sent to.
-     * @throws Error
      * @throws SendingError
      * @throws Forbidden
      */
@@ -80,7 +78,6 @@ class Sender
      * @param Meeting|Call $entity
      * @param ?Invitee[] $targets
      * @return Entity[] Entities an invitation was sent to.
-     * @throws Error
      * @throws SendingError
      * @throws Forbidden
      */
@@ -93,7 +90,6 @@ class Sender
     /**
      * @param ?Invitee[] $targets
      * @return Entity[]
-     * @throws Error
      * @throws SendingError
      * @throws Forbidden
      */
@@ -102,9 +98,9 @@ class Sender
         $this->checkStatus($entity, $type);
 
         $linkList = [
-            'users',
-            'contacts',
-            'leads',
+            Meeting::LINK_USERS,
+            Meeting::LINK_CONTACTS,
+            Meeting::LINK_LEADS,
         ];
 
         $sender = $this->getSender();