Proceedings of the Fourth International Congress of Phonetic Sciences : Proceedings of the 7th international conference on cognitive science Proceedings of the 7th international conference on cognitive science = Proceedings of the third international conference on cognitive science : Proceedings of the Fourth International Congress on Mathematical Education / Proceedings of the 6th international congress of Chinese Mathematicians Proceedings of the 6th international congress of chinese mathematicians Proceedings of the Fourth U.S. National congress of Applied Mechanics : Proceedings of the International Congress of Mathematicians : Proceedings of the 2nd international Congress of Surface Activity.