Payment must be made ``pursuant to a bona fide individual contract
or pursuant to an agreement made as a result of collective bargaining by
representatives of employees.'' It cannot be a onesided affair
determinable only by examination of the employer's books. The employee
must not only be aware of but must have agreed to the method of
compensation in advance of performing the work. Collective bargaining
agreements in general are formal agreements which have been reduced to
writing, but an individual employment contract may be either oral or
written. While there is no requirement in section 7(f) that the
agreement or contract be in writing, it is certainly desirable to reduce
the agreement to writing, since a contract of this character is rather
complicated and proof both of its existence and of its compliance with
the various requirements of the section may be difficult if it is not in
written form. Furthermore, the contract must be ``bona fide.'' This
implies that both the making of the contract and the settlement of its
terms were done in good faith.