Invalid constant API:: with grape and grape-entity

I'm trying to use grape-entity and I'm having trouble with the name-space of my entity class but I cannot figure why.

I have this grape-entity class :

# app/controllers/api/v1/entities/vehicules.rb
module API
  module V1
    module Entities
      class Vehicules < Grape::Entity
        expose :marque
        expose :modele
        expose :user do 
          expose :name
        end
      end
    end
  end
end

And the grape class :

# app/controllers/api/v1/vehicules.rb
module API
  module V1
    class Vehicules < Grape::API
      include API::V1::Defaults
      version 'v1' 
      format :json 


      resource :vehicules do
        desc "Return list of vehicules"
          get do
            #authenticate! @todo
            vehicules = Vehicule.find_by(user_id: params['user_id'])
            present vehicules, with API::V1::Entities::Vehicules
          end

When I call curl http://localhost:3000/api/v1/vehicules?user_id=123 I have in the rails server this message :

Ruby2.1.0/lib/ruby/gems/2.1.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:457:in `load':
app/controllers/api/v1/vehicules.rb:21: syntax error, unexpected tCONSTANT, expecting keyword_do or '{' or (' SyntaxError) 
present vehicules, with API::V1::Entities::Vehicules
                           ^

Any help would be great.

it's with:

present vehicules, with: API::V1::Entities::Vehicules