Langer, S. K. (1953). An introduction to symbolic logic. New York: Dover Publications.
Dyfyniad Arddull ChicagoLanger, Susanne Katherina. An Introduction to Symbolic Logic. New York: Dover Publications, 1953.
Dyfyniad MLALanger, Susanne Katherina. An Introduction to Symbolic Logic. New York: Dover Publications, 1953.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.