Dyfyniad APA

Roberts, T. M., & Roberts, R. D. (1986). Planning and ecology (1st pbk. ed.). Chapman and Hall.

Dyfyniad Arddull Chicago

Roberts, T. M., and R. D. Roberts. Planning and Ecology. 1st pbk. ed. London: Chapman and Hall, 1986.

Dyfyniad MLA

Roberts, T. M., and R. D. Roberts. Planning and Ecology. 1st pbk. ed. Chapman and Hall, 1986.

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