diff --git a/src/gmio_core/internal/min_max.h b/src/gmio_core/internal/min_max.h
new file mode 100644
index 0000000..d9986ee
--- /dev/null
+++ b/src/gmio_core/internal/min_max.h
@@ -0,0 +1,24 @@
+/****************************************************************************
+**
+** GeomIO Library
+** Copyright FougSys (2 Mar. 2015)
+** contact@fougsys.fr
+**
+** This software is a reusable library whose purpose is to provide complete
+** I/O support for various CAD file formats (eg. STL)
+**
+** This software is governed by the CeCILL-B license under French law and
+** abiding by the rules of distribution of free software.  You can  use,
+** modify and/ or redistribute the software under the terms of the CeCILL-B
+** license as circulated by CEA, CNRS and INRIA at the following URL
+** "http://www.cecill.info".
+**
+****************************************************************************/
+
+#ifndef GMIO_INTERNAL_MIN_MAX_H
+#define GMIO_INTERNAL_MIN_MAX_H
+
+#define _GMIO_INTERNAL_MIN(v1, v2)  ((v1) < (v2) ? (v1) : (v2))
+#define _GMIO_INTERNAL_MAX(v1, v2)  ((v1) > (v2) ? (v1) : (v2))
+
+#endif /* GMIO_INTERNAL_MIN_MAX_H */
diff --git a/src/gmio_stl/stla_write.c b/src/gmio_stl/stla_write.c
index dafa5d5..b4cdbca 100644
--- a/src/gmio_stl/stla_write.c
+++ b/src/gmio_stl/stla_write.c
@@ -21,6 +21,7 @@
 #include "stl_error.h"
 
 #include "../gmio_core/error.h"
+#include "../gmio_core/internal/min_max.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -111,8 +112,6 @@ static gmio_bool_t gmio_transfer_flush_buffer(gmio_transfer_t* trsf, size_t n)
   return gmio_stream_write(&trsf->stream, trsf->buffer, sizeof(char), n) == n;
 }
 
-#define _GMIO_INTERNAL_MIN(v1, v2)  ((v1) < (v2) ? (v1) : (v2))
-
 int gmio_stla_write(const gmio_stl_mesh_t* mesh,
                     gmio_transfer_t* trsf,
                     const gmio_stla_write_options_t* options)