Cita APA (7th ed.)

Educators' Progress Service, Randolph, Wis, & Suttles, P. A. Educators guide to free social studies materials (1st- ed.).

Cita Chicago (17th ed.)

Educators' Progress Service, Randolph, Wis, i Patricia A. Suttles. Educators Guide to Free Social Studies Materials. 1st- ed. Randolph, Wis., Educators Progresss Services.

Cita MLA (9th ed.)

Educators' Progress Service, Randolph, Wis, i Patricia A. Suttles. Educators Guide to Free Social Studies Materials. 1st- ed.