Dyfyniad APA

Johnson, S., Haslam, G. W., & Dawson, R. (1993). The great central valley: California's heartland. University of California Press.

Dyfyniad Arddull Chicago

Johnson, Stephen, Gerald W. Haslam, and Robert Dawson. The Great Central Valley: California's Heartland. Berkeley: University of California Press, 1993.

Dyfyniad MLA

Johnson, Stephen, et al. The Great Central Valley: California's Heartland. University of California Press, 1993.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.