Barr, M. (2002). Acyclic models. American Mathematical Society.
Dyfyniad Arddull ChicagoBarr, Michael. Acyclic Models. Providence, R.I.: American Mathematical Society, 2002.
Dyfyniad MLABarr, Michael. Acyclic Models. American Mathematical Society, 2002.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.