diff --git a/docs/attachments/attachments-schema.yaml b/docs/attachments/attachments-schema.yaml
index 191cd46d..2632ec20 100644
--- a/docs/attachments/attachments-schema.yaml
+++ b/docs/attachments/attachments-schema.yaml
@@ -16,7 +16,7 @@ definitions:
           type: number
         category:
           type: string
-          ref: '#/definitions/resourcesCategory'
+          $ref: '#/definitions/resourcesCategory'
         createdAt:
           type: string
           format: date-time
@@ -36,7 +36,7 @@ definitions:
         type: number
       category:
         type: string
-        ref: '#/definitions/resourcesCategory'
+        $ref: '#/definitions/resourcesCategory'
   attachment:
     type: object
     properties:
@@ -52,7 +52,7 @@ definitions:
         type: number
       category:
         type: string
-        ref: '#/definitions/resourcesCategory'
+        $ref: '#/definitions/resourcesCategory'
       createdAt:
         type: string
         format: date-time
diff --git a/docs/chat/chat-schema.yaml b/docs/chat/chat-schema.yaml
index fda2d25d..b6f59432 100644
--- a/docs/chat/chat-schema.yaml
+++ b/docs/chat/chat-schema.yaml
@@ -11,7 +11,7 @@ definitions:
           properties:
             user:
               type: string
-              $ref: '#/components/user'
+              $ref: '#/definitions/user'
             role:
               type: string
         createdAt:
@@ -37,7 +37,7 @@ definitions:
         properties:
           user:
             type: string
-            ref: '#/components/user'
+            $ref: '#/definitions/user'
           role:
             type: string
       createdAt:
diff --git a/docs/chat/chat.yaml b/docs/chat/chat.yaml
index c6c729d4..1732f5a1 100644
--- a/docs/chat/chat.yaml
+++ b/docs/chat/chat.yaml
@@ -40,7 +40,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -118,7 +118,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -128,7 +128,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -138,7 +138,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
@@ -166,7 +166,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -176,7 +176,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -186,7 +186,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
@@ -221,7 +221,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -231,7 +231,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -241,7 +241,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
@@ -270,7 +270,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 400
                 code: INVALID_ID
@@ -280,7 +280,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -290,7 +290,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -300,7 +300,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
@@ -339,7 +339,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 400
                 code: INVALID_ID
@@ -349,7 +349,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -359,7 +359,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -369,7 +369,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
diff --git a/docs/course/course-schema.yaml b/docs/course/course-schema.yaml
index 6baf6ffc..13e4b948 100644
--- a/docs/course/course-schema.yaml
+++ b/docs/course/course-schema.yaml
@@ -12,13 +12,13 @@ definitions:
           type: string
         author:
           type: string
-          ref: '#components/user'
+          $ref: '#definitions/user'
         category:
           type: string
-          ref: '#components/category'
+          $ref: '#definitions/category'
         subject:
           type: string
-          ref: '#components/subject'
+          $ref: '#definitions/subject'
         proficiencyLevel:
           type: array
           items:
@@ -68,13 +68,13 @@ definitions:
         type: string
       author:
         type: string
-        ref: '#components/user'
+        $ref: '#definitions/user'
       category:
         type: string
-        ref: '#components/category'
+        $ref: '#definitions/category'
       subject:
         type: string
-        ref: '#components/subject'
+        $ref: '#definitions/subject'
       proficiencyLevel:
         type: array
         items:
@@ -122,13 +122,13 @@ definitions:
         type: string
       author:
         type: string
-        ref: '#components/user'
+        $ref: '#definitions/user'
       category:
         type: string
-        ref: '#components/category'
+        $ref: '#definitions/category'
       subject:
         type: string
-        ref: '#components/subject'
+        $ref: '#definitions/subject'
       proficiencyLevel:
         type: array
         items:
diff --git a/docs/finishedQuiz/finishedQuiz.yaml b/docs/finishedQuiz/finishedQuiz.yaml
index 360e341b..9544940d 100644
--- a/docs/finishedQuiz/finishedQuiz.yaml
+++ b/docs/finishedQuiz/finishedQuiz.yaml
@@ -63,7 +63,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -73,7 +73,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -132,7 +132,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 401
                 code: UNAUTHORIZED
@@ -142,7 +142,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 403
                 code: FORBIDDEN
@@ -152,7 +152,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: '#/components/Error'
+                $ref: '#/definitions/Error'
               example:
                 status: 404
                 code: DOCUMENT_NOT_FOUND
diff --git a/docs/lesson/lesson-schema.yaml b/docs/lesson/lesson-schema.yaml
index 6a7b28d6..a8c70216 100644
--- a/docs/lesson/lesson-schema.yaml
+++ b/docs/lesson/lesson-schema.yaml
@@ -36,7 +36,7 @@ definitions:
         type: string
       author:
         type: string
-        $ref: '#components/user'
+        $ref: '#definitions/user'
       title:
         type: string
       description:
diff --git a/docs/message/message-schema.yaml b/docs/message/message-schema.yaml
index 38600d9c..f83080ac 100644
--- a/docs/message/message-schema.yaml
+++ b/docs/message/message-schema.yaml
@@ -14,12 +14,12 @@ definitions:
     properties:
       author:
         type: string
-        ref: '#/components/user'
+        $ref: '#/definitions/user'
       text:
         type: string
       chat:
         type: string
-        ref: '#/components/chat'
+        $ref: '#/definitions/chat'
   message:
     type: object
     properties:
@@ -30,7 +30,7 @@ definitions:
         properties:
           _id:
             type: string
-            ref: '#/components/user'
+            $ref: '#/definitions/user'
           photo:
             type: string
       authorRole:
@@ -46,7 +46,7 @@ definitions:
         type: boolean
       chat:
         type: string
-        ref: '#/components/chat'
+        $ref: '#/definitions/chat'
       createdAt:
         type: string
         format: date-time
diff --git a/docs/note/note-schema.yaml b/docs/note/note-schema.yaml
index 0b88bffb..8906bdb3 100644
--- a/docs/note/note-schema.yaml
+++ b/docs/note/note-schema.yaml
@@ -10,7 +10,7 @@ definitions:
           type: string
         author:
           type: string
-          ref: '#components/user'
+          $ref: '#definitions/user'
         isPrivate:
           type: boolean
         createdAt:
@@ -35,7 +35,7 @@ definitions:
         type: string
       author:
         type: string
-        ref: '#components/user'
+        $ref: '#definitions/user'
       isPrivate:
         type: boolean
       createdAt:
diff --git a/docs/offer/offer-schema.yaml b/docs/offer/offer-schema.yaml
index cf57036c..c72d79c3 100644
--- a/docs/offer/offer-schema.yaml
+++ b/docs/offer/offer-schema.yaml
@@ -39,19 +39,19 @@ definitions:
           type: string
         author:
           type: string
-          ref: '#components/user'
+          $ref: '#definitions/user'
         enrolledUsers:
           type: array
-          ref: '#components/user'
+          $ref: '#definitions/user'
         subject:
           type: string
-          ref: '#components/subject'
+          $ref: '#definitions/subject'
         category:
           type: string
-          ref: '#components/category'
+          $ref: '#definitions/category'
         chatId:
           type: string
-          ref: '#/components/chat'
+          $ref: '#/definitions/chat'
         status:
           type: string
           enum:
@@ -109,13 +109,13 @@ definitions:
         type: string
       enrolledUsers:
         type: array
-        ref: '#components/user'
+        $ref: '#definitions/user'
       subject:
         type: string
-        ref: '#components/subject'
+        $ref: '#definitions/subject'
       category:
         type: string
-        ref: '#components/category'
+        $ref: '#definitions/category'
       status:
         type: string
         enum:
@@ -169,19 +169,19 @@ definitions:
         type: string
       author:
         type: string
-        ref: '#components/user'
+        $ref: '#definitions/user'
       enrolledUsers:
         type: array
-        ref: '#components/user'
+        $ref: '#definitions/user'
       subject:
         type: string
-        ref: '#components/subject'
+        $ref: '#definitions/subject'
       category:
         type: string
-        ref: '#components/category'
+        $ref: '#definitions/category'
       chatId:
         type: string
-        ref: '#/components/chat'
+        $ref: '#/definitions/chat'
       status:
         type: string
         enum:
diff --git a/docs/questions/question.schema.yaml b/docs/questions/question.schema.yaml
index eab4abfa..ffa1e2c8 100644
--- a/docs/questions/question.schema.yaml
+++ b/docs/questions/question.schema.yaml
@@ -21,10 +21,10 @@ definitions:
                 type: boolean
         author:
           type: string
-          ref: '#/components/user'
+          $ref: '#/definitions/user'
         category:
           type: string
-          ref: '#/definitions/resourcesCategory'
+          $ref: '#/definitions/resourcesCategory'
         createdAt:
           type: string
           format: date-time
@@ -51,7 +51,7 @@ definitions:
         type: string
       category:
         type: string
-        ref: '#/definitions/resourcesCategory'
+        $ref: '#/definitions/resourcesCategory'
   question:
     type: object
     properties:
@@ -72,10 +72,10 @@ definitions:
               type: boolean
       author:
         type: string
-        ref: '#/components/user'
+        $ref: '#/definitions/user'
       category:
         type: string
-        ref: '#/definitions/resourcesCategory'
+        $ref: '#/definitions/resourcesCategory'
       createdAt:
         type: string
         format: date-time
diff --git a/docs/quiz/quiz-schema.yaml b/docs/quiz/quiz-schema.yaml
index 9990657a..5431c3c8 100644
--- a/docs/quiz/quiz-schema.yaml
+++ b/docs/quiz/quiz-schema.yaml
@@ -50,13 +50,13 @@ definitions:
       category:
         type: string
         description: _id
-        ref: '#/definitions/resourcesCategory'
+        $ref: '#/definitions/resourcesCategory'
       items:
         type: array
         items:
           type: string
           description: _id
-          ref: '#/components/question'
+          $ref: '#/definitions/question'
       settings:
         type: object
         properties:
diff --git a/docs/subject/subject-schema.yaml b/docs/subject/subject-schema.yaml
index e9b68012..de133ca9 100644
--- a/docs/subject/subject-schema.yaml
+++ b/docs/subject/subject-schema.yaml
@@ -42,7 +42,7 @@ definitions:
         type: string
       category:
         type: string
-        $ref: '#/components/category'
+        $ref: '#/definitions/category'
   subject:
     type: object
     properties:
@@ -52,7 +52,7 @@ definitions:
         type: string
       category:
         type: string
-        $ref: '#/components/category'
+        $ref: '#/definitions/category'
       totalOffers:
         type: object
         properties: