(1998). Economics: A student's guide (4th ed.). Pearson Education Limited.
Cita Chicago (17th ed.)Economics: A Student's Guide. 4th ed. England: Pearson Education Limited, 1998.
Cita MLA (9th ed.)Economics: A Student's Guide. 4th ed. Pearson Education Limited, 1998.
Atenció: Aquestes cites poden no estar 100% correctes.