diff --git a/src/GRANULAR/fix_wall_gran_region.cpp b/src/GRANULAR/fix_wall_gran_region.cpp
index 3ed7cf3d90..96b1f5071f 100644
--- a/src/GRANULAR/fix_wall_gran_region.cpp
+++ b/src/GRANULAR/fix_wall_gran_region.cpp
@@ -15,9 +15,9 @@
    Contributing authors: Dan Bolintineanu (SNL)
 ------------------------------------------------------------------------- */
 
-#include "math.h"
-#include "stdlib.h"
-#include "string.h"
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
 #include "fix_wall_gran_region.h"
 #include "region.h"
 #include "atom.h"
diff --git a/src/USER-DPD/fix_dpd_energy.cpp b/src/USER-DPD/fix_dpd_energy.cpp
index e6b7a9e83e..05907a5fcf 100644
--- a/src/USER-DPD/fix_dpd_energy.cpp
+++ b/src/USER-DPD/fix_dpd_energy.cpp
@@ -11,8 +11,8 @@
    See the README file in the top-level LAMMPS directory.
 ------------------------------------------------------------------------- */
 
-#include "stdio.h"
-#include "string.h"
+#include <stdio.h>
+#include <string.h>
 #include "fix_dpd_energy.h"
 #include "atom.h"
 #include "force.h"