db/conf/ht/AkscynHORW89.html Robert M. Akscyn Frank G. Halasz Tim Oren Victor A. Riley Lawrence Welch Interchanging Hypertexts. 379-381 HT1989/P379.pdf 1989 conf/ht/89 Hypertext db/conf/ht/ht89.html#AkscynHORW89