In December 1968, the report on the programming language ALGOL 68 was published. On 20–24 July 1970, a working conference was arranged by the International Federation for Information Processing (IFIP) to discuss the problems of implementing the language. A small team from RRE attended to present their compiler, written by I. F. Currie, Susan G. Bond, and J. D. Morrison. ALGOL 68 was complex: implementing it was estimated to need up to 100 man-years, using multi-pass compilers with up to seven passes. The RRE team described how they had already implemented a one-pass compiler, which was already in production for engineering and scientific uses. It was the first working version of ALGOL 68.