APA

Javna J., Zuckerman S., Calwell C., Pacific Gas and Electric Company & Earth Works Group (U.S.). (1990). 30 simple energy things you can do to save the earth. [San Francisco, Calif.?]: Pacific Gas & Electric.

Chicago

Javna John, Zuckerman Seth, Calwell Chris, Pacific Gas and Electric Company and Earth Works Group (U.S.). 1990. 30 simple energy things you can do to save the earth. [San Francisco, Calif.?]: Pacific Gas & Electric.

Harvard

Javna J., Zuckerman S., Calwell C., Pacific Gas and Electric Company and Earth Works Group (U.S.). (1990). 30 simple energy things you can do to save the earth. [San Francisco, Calif.?]: Pacific Gas & Electric.

MLA

Javna John, Zuckerman Seth, Calwell Chris, Pacific Gas and Electric Company and Earth Works Group (U.S.). 30 simple energy things you can do to save the earth. [San Francisco, Calif.?]: Pacific Gas & Electric. 1990.