Potter, K. D. (1999). Educators guide to finding resources in the public domain. Phi Delta Kappa Educational Foundation.
Cita Chicago (17th ed.)Potter, Kenyon David. Educators Guide to Finding Resources in the Public Domain. USA: Phi Delta Kappa Educational Foundation, 1999.
Cita MLA (9th ed.)Potter, Kenyon David. Educators Guide to Finding Resources in the Public Domain. Phi Delta Kappa Educational Foundation, 1999.
Atenció: Aquestes cites poden no estar 100% correctes.