doc: Remove dead links

The web pages of Andy Dong at Berkeley don't exist anymore, and he is no
longer there.

diff --git a/doc/src/sgml/cube.sgml b/doc/src/sgml/cube.sgml
index e2da68556d561a870e3a9a89de21f4e625a64ce5..60bd84bf22ba853e574f9e32fe0192c12d535eaf 100644 (file)
--- a/doc/src/sgml/cube.sgml
+++ b/doc/src/sgml/cube.sgml
@@ -391,10 +391,7 @@ t
    My thanks are primarily to Prof. Joe Hellerstein
    () for elucidating the
    gist of the GiST (), and
-   to his former student, Andy Dong (
-   url="http://best.me.berkeley.edu/~adong/">), for his example
-   written for Illustra,
-   .
+   to his former student Andy Dong for his example written for Illustra.
    I am also grateful to all Postgres developers, present and past, for
    enabling myself to create my own world and live undisturbed in it. And I
    would like to acknowledge my gratitude to Argonne Lab and to the