Cita APA (7a ed.)

Looper, K., & Grizenko, N. (1999). Risk and protective factors scale: Reliability and validity in preadolescents. [s.n.].

Cita Chicago Style (17a ed.)

Looper, Karl, y Natalie Grizenko. Risk and Protective Factors Scale: Reliability and Validity in Preadolescents. [S.l.]: [s.n.], 1999.

Cita MLA (9a ed.)

Looper, Karl, y Natalie Grizenko. Risk and Protective Factors Scale: Reliability and Validity in Preadolescents. [s.n.], 1999.