diff --git a/doc/ack.texi b/doc/ack.texi
index 862bf0b00..0e5007194 100644
--- a/doc/ack.texi
+++ b/doc/ack.texi
@@ -53,6 +53,10 @@ Bugfixes, documentation, encouragement, and code has been contributed by:
 @email{bmay@@snoopy.apana.org.au}
 @item Chaskiel M Grundman
 @email{cg2v@@andrew.cmu.edu}
+@item Richard Nyberg
+@email{rnyberg@@it.su.se}
+@item Frank van der Linden
+@email{fvdl@@netbsd.org}
 @item and we hope that those not mentioned here will forgive us.
 @end table