diff --git a/cmake/externals/glm/CMakeLists.txt b/cmake/externals/glm/CMakeLists.txt
index b1aed7dd7f..0ca4aa3cb2 100644
--- a/cmake/externals/glm/CMakeLists.txt
+++ b/cmake/externals/glm/CMakeLists.txt
@@ -12,4 +12,4 @@ ExternalProject_Add(
 ExternalProject_Get_Property(${EXTERNAL_NAME} INSTALL_DIR)
 
 string(TOUPPER ${EXTERNAL_NAME} EXTERNAL_NAME_UPPER)
-set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE TYPE STRING)
\ No newline at end of file
+set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE)
\ No newline at end of file
diff --git a/cmake/externals/gverb/CMakeLists.txt b/cmake/externals/gverb/CMakeLists.txt
index 19a44781b1..463ee26ff0 100644
--- a/cmake/externals/gverb/CMakeLists.txt
+++ b/cmake/externals/gverb/CMakeLists.txt
@@ -16,10 +16,10 @@ ExternalProject_Add(
 ExternalProject_Get_Property(${EXTERNAL_NAME} INSTALL_DIR)
 
 string(TOUPPER ${EXTERNAL_NAME} EXTERNAL_NAME_UPPER)
-set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE TYPE STRING)
+set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE TYPE "Path to gverb include directory")
 
 if (WIN32) 
-  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/gverb.lib CACHE TYPE STRING)
+  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/gverb.lib CACHE TYPE "List of gverb libraries")
 else ()
-  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libgverb.a CACHE TYPE STRING)
+  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libgverb.a CACHE TYPE "List of gverb libraries")
 endif ()
\ No newline at end of file
diff --git a/cmake/externals/soxr/CMakeLists.txt b/cmake/externals/soxr/CMakeLists.txt
index fcd28d4db5..2c8dd5de7d 100644
--- a/cmake/externals/soxr/CMakeLists.txt
+++ b/cmake/externals/soxr/CMakeLists.txt
@@ -16,13 +16,13 @@ ExternalProject_Add(
 ExternalProject_Get_Property(${EXTERNAL_NAME} INSTALL_DIR)
 
 string(TOUPPER ${EXTERNAL_NAME} EXTERNAL_NAME_UPPER)
-set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE TYPE STRING)
+set(${EXTERNAL_NAME_UPPER}_INCLUDE_DIRS ${INSTALL_DIR}/include CACHE TYPE "List of soxr include directories")
 
 if (WIN32) 
-  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/soxr.lib CACHE TYPE STRING)
-  set(${EXTERNAL_NAME_UPPER}_DLL_PATH ${INSTALL_DIR}/bin CACHE TYPE STRING)
+  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/soxr.lib CACHE TYPE "List of soxr libraries")
+  set(${EXTERNAL_NAME_UPPER}_DLL_PATH ${INSTALL_DIR}/bin CACHE TYPE "Path to soxr dll")
 elseif (APPLE)
-  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libsoxr.dylib CACHE TYPE STRING)
+  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libsoxr.dylib CACHE TYPE "List of soxr libraries")
 else ()
-  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libsoxr.so CACHE TYPE STRING)
+  set(${EXTERNAL_NAME_UPPER}_LIBRARIES ${INSTALL_DIR}/lib/libsoxr.so CACHE TYPE "List of soxr libraries")
 endif ()
\ No newline at end of file