Layard, R. (1994). Cost-benefit analysis (2nd ed.). Cambridge University Press.
Chicago Style aipamenaLayard, Richard. Cost-benefit Analysis. 2nd ed. Cambridge: Cambridge University Press, 1994.
MLA aipamenaLayard, Richard. Cost-benefit Analysis. 2nd ed. Cambridge University Press, 1994.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.