Nikolay K. Diakov Zlatko Zlatev Stanislav Pokraev Composition of Negotiation Protocols for E-Commerce Applications. 418-423 2005 conf/eee/2005 EEE http://doi.ieeecomputersociety.org/10.1109/EEE.2005.50 db/conf/eee/eee2005.html#DiakovZP05