Quoc Bao Vo Norman Y. Foo Solving the Ramification Problem: Causal Propagation in an Argumentation-Theoretic Approach. 49-59 2002 conf/pricai/2002 PRICAI http://link.springer.de/link/service/series/0558/bibs/2417/24170049.htm db/conf/pricai/pricai2002.html#VoF02