Cita APA (7th ed.)

BERMAN, L., & EVANS, J. Exploring the cosmos.-- Ed.4. Little.

Cita Chicago (17th ed.)

BERMAN, Louis, i J.C EVANS. Exploring the Cosmos.-- Ed.4. Boston: Little.

Cita MLA (9th ed.)

BERMAN, Louis, i J.C EVANS. Exploring the Cosmos.-- Ed.4. Little.