Brown, M. (1988). World phosphates supply to the year 2000. OECD.
Cita Chicago (17th ed.)Brown, Martin. World Phosphates Supply to the Year 2000. Paris: OECD, 1988.
Cita MLA (9th ed.)Brown, Martin. World Phosphates Supply to the Year 2000. OECD, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.