Cita APA (7th ed.)

Britannica Corporation. (1990). Geology [videorecording]: Rocks that form in the earth's surface, rocks that originate underground. Encyclopedia Britannica Educational Corporation.

Cita Chicago (17th ed.)

Britannica Corporation. Geology [videorecording]: Rocks That Form in the Earth's Surface, Rocks That Originate Underground. Chicago: Encyclopedia Britannica Educational Corporation, 1990.

Cita MLA (9th ed.)

Britannica Corporation. Geology [videorecording]: Rocks That Form in the Earth's Surface, Rocks That Originate Underground. Encyclopedia Britannica Educational Corporation, 1990.