diff --git a/Building-for-Ubuntu-16.04.md b/Building-for-Ubuntu-16.04.md
index e47a25d..12503a0 100644
--- a/Building-for-Ubuntu-16.04.md
+++ b/Building-for-Ubuntu-16.04.md
@@ -15,6 +15,11 @@ The following instructions install `cmake` to `~/cmake`:
     sudo apt-get update
     sudo apt-get install gcc-7 g++-7
 
+Remove the PPA (optional):
+
+    sudo add-apt-repository --remove ppa:jonathonf/gcc-7.1
+    sudo apt-get update
+
 ### Other prerequisites
 
     sudo apt-get install build-essential git libcurl4-openssl-dev libqt5opengl5-dev libsdl2-dev libssl-dev qtbase5-dev wget xorg-dev