diff --git a/src/classes/PMusrCanvas.cpp b/src/classes/PMusrCanvas.cpp
index 5c3f6453..de383a93 100644
--- a/src/classes/PMusrCanvas.cpp
+++ b/src/classes/PMusrCanvas.cpp
@@ -28,6 +28,7 @@
  ***************************************************************************/
 
 #include <iostream>
+#include <iomanip>
 #include <fstream>
 using namespace std;