Helen Dwight Reid Educational Foundation. (1989). Preventing school failure. Heldref Publications.
Cita Chicago (17th ed.)Helen Dwight Reid Educational Foundation. Preventing School Failure. Washington, D.C.: Heldref Publications, 1989.
Cita MLA (9th ed.)Helen Dwight Reid Educational Foundation. Preventing School Failure. Heldref Publications, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.