Cita APA (7a ed.)

National School Safety Center. Malibu Beach, Calif. , & Ackley, N. (1990). Gangs in schools: Breaking up is hard to do (6. print.).

Cita Chicago Style (17a ed.)

National School Safety Center. Malibu Beach, Calif. , y Nancy Ackley. Gangs in Schools: Breaking Up Is Hard to Do. 6. print. Malibu, Calif, 1990.

Cita MLA (9a ed.)

National School Safety Center. Malibu Beach, Calif. , y Nancy Ackley. Gangs in Schools: Breaking Up Is Hard to Do. 6. print. 1990.