Cita APA (7th ed.)
Reif, J., Whittle, J., & Thurmond, M. E. Services. World Trade Press.
Cita Chicago (17th ed.)
Reif, Joe, Janet Whittle, i Molly E. Thurmond. Services. US: World Trade Press.
Cita MLA (9th ed.)
Reif, Joe, et al. Services. World Trade Press.
Atenció: Aquestes cites poden no estar 100% correctes.