Upon ordering the return of a child or issuing an order concerning rights of access under this Convention, the judicial or administrative authorities may, where appropriate, direct the person who removed or retained the child, or who prevented the exercise of rights of access, to pay necessary expenses incurred by or on behalf of the applicant, including travel expenses, any costs incurred or payments made for locating the child, the costs of legal representation of the applicant, and those of returning the child.