Servey, R. E. (1982). Social studies. Scott, Foresman.
Cita Chicago (17th ed.)Servey, Richard E. Social Studies. Scott, Foresman, 1982.
Cita MLA (9th ed.)Servey, Richard E. Social Studies. Scott, Foresman, 1982.
Atenció: Aquestes cites poden no estar 100% correctes.