@book{1989--issac
,title={{International symposium on symbolic and algebraic computation, ISSAC '89, Portland, Oregon, USA, July 17--19, 1989}}
,booktitle={{International symposium on symbolic and algebraic computation, ISSAC '89, Portland, Oregon, USA, July 17--19, 1989}}
,publisher={Association for Computing Machinery}
,address={New York}
,year={1989}
}