diff --git a/app/models/participation.rb b/app/models/participation.rb
index 42531d3..bfd700e 100644
--- a/app/models/participation.rb
+++ b/app/models/participation.rb
@@ -1,6 +1,6 @@
 class Participation < ActiveRecord::Base
-  belongs_to :participant, class_name: User
-  has_one :participant_with_personal_profile, class_name: Participant
+  belongs_to :participant, class_name: 'User'
+  has_one :participant_with_personal_profile, class_name: 'Participant'
   belongs_to :event
   validates :participant_id, presence: true
   scope :approved, ->() { where approved: true }