Cita APA (7a ed.)

Perlman, R., & Gilbert, C. (1987). The prospect for commodities. [s.n.].

Cita Chicago Style (17a ed.)

Perlman, Robert, y Christopher Gilbert. The Prospect for Commodities. [S.l.]: [s.n.], 1987.

Cita MLA (9a ed.)

Perlman, Robert, y Christopher Gilbert. The Prospect for Commodities. [s.n.], 1987.