1997.05.19 18:26 "CCITT Rec. T4/T6 Documents", by Perry Yuan

CCITT Recommendation T.4 document available at http://www.igd.fhg.de/icib/telecom/ccitt/rec_t.4/gen.html

CCITT Recommendation T.6 document available at http://www.igd.fhg.de/www/projects/icib/telecom/ccitt/rec_t.6/gen.html