Add concerns module to Model

I have a model class called Person. The person class has a attribute called car.

Now I would like to define a module in the concerns model called Person::Car::HasProducer

The module should look like that:

module HasProducer

   def produced_by_toyota?
     car == "Prius"
   end

   def produced_by_bmw?
     car == "X3" || car == "X5"
   end 
end

I would like to locate this file under: concerns/person/car/has_producer.rb

In the Person-class I tried to include it like that:

class Person
  include Person::Car::HasProducer

But there I get the error: Unable to autoload constant Person::Car::HasProducer

I tried different combinations of modules/classes but none of the constellation worked for me.

What do I have to do so that has_producer.rb get's found as Person::Car::HasProducer?