ACM Hypertext Conference

 ACM Hypertext Conference  is an annual academic conference on the subject of hypertext and typically the web, where both XFN and XMDP were presented in poster sessions in the mid 2000s, and in 1991 HTML was submitted but rejected (TimBL gave a poster); and their event sites for some years either died or were taken over by squatters (like ht04.org for 2004).