add ubuntu package to INSTALL

diff --git a/INSTALL b/INSTALL
index 78ca13ad0f3ad7f440220953e5882c93c55ea4ac..4c1bd17c54dd9096a58be46d8a1bdb08a6d8870b 100644 (file)
--- a/INSTALL
+++ b/INSTALL
@@ -8,7 +8,7 @@ Install Prerequisites
 been ported to Xerces 3. For Debian or Ubuntu, the required packages
 can be installed with the following
 
-$ sudo apt install wget build-essential libx11-dev libxerces-c-dev
+$ sudo apt install wget build-essential libx11-dev libxerces-c-dev libxext-dev
 
 2. Run the following command