Gaya APA

BIRDSALL, S, S., FLORIN, J. (1992). OUTLINE OF AMERICAN GEOGRAPHY: REGIONAL LANDSCAPES OF THE UNITED STATES (Ed. IV). AMERIKA: JOHN WILEY & SONS, INC..

Gaya MLA

BIRDSALL, STEPHEN, S.., FLORIN, JOHN. "OUTLINE OF AMERICAN GEOGRAPHY: REGIONAL LANDSCAPES OF THE UNITED STATES". Ed. IV AMERIKA: JOHN WILEY & SONS, INC., 1992. Text.