diff --git a/CMakeLists.txt b/CMakeLists.txt
index db2604cc1d4149eb3aa1678525dbdf91e3d25599..72a87f70344658bd7853a8d9f275104c3ea803bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,4 @@
-cmake_minimum_required (VERSION 2.6)
-
+cmake_minimum_required(VERSION 3.1.0 FATAL_ERROR)
 
 if("${PROJECT_NAME}" STREQUAL "")
     message("Setting project name to OpenVolumeMesh")
@@ -13,11 +12,15 @@ endif()
 set (CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
 set (CMAKE_DEBUG_POSTFIX "d")
 
+
 # Enable bigobj on MSVC Windows debug mode
 if ( MSVC )
    add_compile_options("$<IF:$<CXX_COMPILER_ID:MSVC>,$<$<CONFIG:DEBUG>:/bigobj>,>")
 endif()
 
+if (WIN32)
+  add_definitions( -D_USE_MATH_DEFINES -DNOMINMAX  )
+endif ()
 
 # include our cmake files
 include (ACGCommon)
@@ -26,11 +29,6 @@ acg_get_version ()
 
 include (ACGOutput)
 
-if (WIN32)
-  add_definitions(
-      -D_USE_MATH_DEFINES -DNOMINMAX
-  )
-endif ()
 
 # ========================================================================
 # Call the subdirectories with the projects
diff --git a/documentation/doxy.config.in b/documentation/doxy.config.in
index 573b17301c233dd8fea1500cb67d25e7a81ff54a..30e8ace9eac83177c9e9100b228e58d1d6982f86 100644
--- a/documentation/doxy.config.in
+++ b/documentation/doxy.config.in
@@ -1,4 +1,4 @@
-# Doxyfile 1.8.12
+# Doxyfile 1.8.13
 
 # This file describes the settings to be used by the documentation system
 # doxygen (www.doxygen.org) for a project.
@@ -2387,6 +2387,11 @@ DIAFILE_DIRS           =
 
 PLANTUML_JAR_PATH      =
 
+# When using plantuml, the PLANTUML_CFG_FILE tag can be used to specify a
+# configuration file for plantuml.
+
+PLANTUML_CFG_FILE      =
+
 # When using plantuml, the specified paths are searched for files specified by
 # the !include statement in a plantuml block.