diff --git a/external/external_build.cmake b/external/external_build.cmake
index 780dff6..43e0021 100644
--- a/external/external_build.cmake
+++ b/external/external_build.cmake
@@ -249,10 +249,14 @@ ELSE (INTERNAL_BOOST)
   find_package(Boost 1.69 QUIET)
   if (NOT Boost_FOUND)
     cmessage(CWARNING "Boost >= 1.69 was not found")
+  else()
+    cmessage(STATUS "Boost has been found (version=${Boost_VERSION})")
   endif()
-  if (${Boost_VERSION} VERSION_GREATER_EQUAL 1.70.0)
-    set(Boost_DEP Boost::headers)
-    set(Boost_TARGET Boost::headers)
+  if (Boost_VERSION)
+    if (${Boost_VERSION} VERSION_GREATER_EQUAL 1.70.0)
+      set(Boost_DEP Boost::headers)
+      set(Boost_TARGET Boost::headers)
+    endif()
   endif()
 endif (INTERNAL_BOOST)
 mark_as_advanced(Boost_INCLUDE_DIRS Boost_LIBRARIES)