diff --git a/src/RestClientBuilder.php b/src/RestClientBuilder.php
index e80edb8..68546c3 100644
--- a/src/RestClientBuilder.php
+++ b/src/RestClientBuilder.php
@@ -56,6 +56,12 @@
 
 final class RestClientBuilder
 {
+    public const SUGGEST_ADDRESSES_CLIENT    = 'SUGGEST-ADDRESSES-CLIENT';
+    public const SUGGEST_ORGANIZATION_CLIENT = 'SUGGEST-ORGANIZATION-CLIENT';
+    public const SUGGEST_FULLNAME_CLIENT     = 'SUGGEST-FULLNAME-CLIENT';
+    public const CLEAN_ADDRESSES_CLIENT      = 'CLEAN-ADDRESSES-CLIENT';
+    public const CLEAN_FULLNAME_CLIENT       = 'CLEAN-FULLNAME-CLIENT';
+
     private PsrHttpClient $client;
 
     private Serializer $serializer;
@@ -200,7 +206,7 @@ public function withClient(PsrHttpClient $client): self
      */
     public function createCleanFullNameClient(string $url = 'https://cleaner.dadata.ru'): CleanFullNameClient
     {
-        $new = $this->withSource('CLEAN-FULLNAME-CLIENT');
+        $new = $this->withSource(self::CLEAN_FULLNAME_CLIENT);
 
         return new RestCleanFullNameClient(
             $new->serializer,
@@ -214,11 +220,11 @@ public function createCleanFullNameClient(string $url = 'https://cleaner.dadata.
     /**
      * @param non-empty-string $url
      */
-    public function createSuggestAddressClient(string $url = 'https://suggestions.dadata.ru'): SuggestAddressClient
+    public function createSuggestFullNameClient(string $url = 'https://suggestions.dadata.ru'): RestSuggestFullNameClient
     {
-        $new = $this->withSource('SUGGEST-ADDRESSES-CLIENT');
+        $new = $this->withSource(self::SUGGEST_FULLNAME_CLIENT);
 
-        return new RestSuggestAddressClient(
+        return new RestSuggestFullNameClient(
             $new->serializer,
             new HttpClient(
                 new ConfigurationClient($new->apiKey, $new->secretKey, $url),
@@ -230,11 +236,11 @@ public function createSuggestAddressClient(string $url = 'https://suggestions.da
     /**
      * @param non-empty-string $url
      */
-    public function createSuggestOrganizationClient(string $url = 'https://suggestions.dadata.ru'): SuggestOrganizationClient
+    public function createSuggestAddressClient(string $url = 'https://suggestions.dadata.ru'): SuggestAddressClient
     {
-        $new = $this->withSource('SUGGEST-ORGANIZATION-CLIENT');
+        $new = $this->withSource(self::SUGGEST_ADDRESSES_CLIENT);
 
-        return new RestSuggestOrganizationClient(
+        return new RestSuggestAddressClient(
             $new->serializer,
             new HttpClient(
                 new ConfigurationClient($new->apiKey, $new->secretKey, $url),
@@ -246,11 +252,11 @@ public function createSuggestOrganizationClient(string $url = 'https://suggestio
     /**
      * @param non-empty-string $url
      */
-    public function createSuggestFullNameClient(string $url = 'https://suggestions.dadata.ru'): RestSuggestFullNameClient
+    public function createSuggestOrganizationClient(string $url = 'https://suggestions.dadata.ru'): SuggestOrganizationClient
     {
-        $new = $this->withSource('SUGGEST-FULLNAME-CLIENT');
+        $new = $this->withSource(self::SUGGEST_ORGANIZATION_CLIENT);
 
-        return new RestSuggestFullNameClient(
+        return new RestSuggestOrganizationClient(
             $new->serializer,
             new HttpClient(
                 new ConfigurationClient($new->apiKey, $new->secretKey, $url),
@@ -264,7 +270,7 @@ public function createSuggestFullNameClient(string $url = 'https://suggestions.d
      */
     public function createCleanAddressClient(string $url = 'https://cleaner.dadata.ru'): CleanAddressClient
     {
-        $new = $this->withSource('CLEAN-ADDRESSES-CLIENT');
+        $new = $this->withSource(self::CLEAN_ADDRESSES_CLIENT);
 
         return new RestCleanAddressClient(
             $new->serializer,