Brown, L. R., & Eckholm, E. P. (1974). By bread alone. Praeger.
Dyfyniad Arddull ChicagoBrown, Lester Russell, and Erik P. Eckholm. By Bread Alone. New York: Praeger, 1974.
Dyfyniad MLABrown, Lester Russell, and Erik P. Eckholm. By Bread Alone. Praeger, 1974.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.