diff --git a/src/format.c b/src/format.c
index 9207814..0d7b7cf 100644
--- a/src/format.c
+++ b/src/format.c
@@ -27,6 +27,7 @@
  * 
  */
 
+#include <ctype.h>
 #include <string.h>
 #include "queue.h"
 #include "stack.h"
diff --git a/src/odt.c b/src/odt.c
index 2674871..6316bd0 100644
--- a/src/odt.c
+++ b/src/odt.c
@@ -31,6 +31,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <sys/wait.h>
 #include "odt.h"
 #include "options.h"
 
diff --git a/src/xslt.c b/src/xslt.c
index 531e89d..5363db9 100644
--- a/src/xslt.c
+++ b/src/xslt.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <libxml/tree.h>
 #include <libxslt/xslt.h>