diff --git a/accountant/api/views/operations.py b/accountant/api/views/operations.py
index 846e7dd..f8e0026 100644
--- a/accountant/api/views/operations.py
+++ b/accountant/api/views/operations.py
@@ -24,12 +24,12 @@ from .. import api
 
 from ..models.operations import Operation
 
-from ..fields import Object
-
 from .users import requires_auth
 
+from ..fields import Object
 
-resource_fields = {
+
+operation_with_sold_model = {
     'id': fields.Integer(default=None),
     'operation_date': fields.DateTime(dt_format='iso8601'),
     'label': fields.String,
@@ -65,7 +65,7 @@ range_parser.add_argument('end', type=lambda a: dateutil.parser.parse(a))
 
 class OperationListResource(Resource):
     @requires_auth
-    @marshal_with_field(fields.List(Object(resource_fields)))
+    @marshal_with_field(fields.List(Object(operation_with_sold_model)))
     def get(self):
         data = range_parser.parse_args()
 
@@ -77,7 +77,7 @@ class OperationListResource(Resource):
         ).all(), 200
 
     @requires_auth
-    @marshal_with_field(Object(resource_fields))
+    @marshal_with_field(Object(operation_model))
     def post(self):
         data = parser.parse_args()
 
@@ -90,7 +90,7 @@ class OperationListResource(Resource):
 
 class OperationResource(Resource):
     @requires_auth
-    @marshal_with_field(Object(resource_fields))
+    @marshal_with_field(Object(operation_model))
     def get(self, id):
         """
         Get operation.
@@ -103,7 +103,7 @@ class OperationResource(Resource):
         return operation, 200
 
     @requires_auth
-    @marshal_with_field(Object(resource_fields))
+    @marshal_with_field(Object(operation_model))
     def post(self, id):
         data = parser.parse_args()
 
@@ -124,7 +124,7 @@ class OperationResource(Resource):
         return operation, 200
 
     @requires_auth
-    @marshal_with_field(Object(resource_fields))
+    @marshal_with_field(Object(operation_model))
     def delete(self, id):
         operation = db.session.query(Operation).get(id)