diff --git a/FreeType/CMakeLists.txt b/FreeType/CMakeLists.txt
index 7cf2ce9e..8d06353f 100644
--- a/FreeType/CMakeLists.txt
+++ b/FreeType/CMakeLists.txt
@@ -70,7 +70,12 @@ endif ()
 
 # set to use FT_CONFIG_OPTION_SYSTEM_ZLIB...or in other words...another zlib
 target_compile_definitions(FreeType PUBLIC FT2_BUILD_LIBRARY=1 FT_CONFIG_OPTION_SYSTEM_ZLIB=1)   
-target_link_libraries(FreeType PDFHummus::Zlib)
+if(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(FreeType ZLIB::ZLIB)
+else(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(FreeType PDFHummus::Zlib)
+endif(USING_UNBUNDLED_ZLIB)
+
 
 target_include_directories(FreeType
     PRIVATE
diff --git a/LibPng/CMakeLists.txt b/LibPng/CMakeLists.txt
index 916d4476..1129c0bb 100644
--- a/LibPng/CMakeLists.txt
+++ b/LibPng/CMakeLists.txt
@@ -45,8 +45,11 @@ if(WIN32 AND BUILD_SHARED_LIBS)
     target_compile_definitions(LibPng PUBLIC PNG_USE_DLL)
 endif()
 
-target_link_libraries(LibPng PDFHummus::Zlib)
-
+if(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(LibPng ZLIB::ZLIB)
+else(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(LibPng PDFHummus::Zlib)
+endif(USING_UNBUNDLED_ZLIB)
 
 install(TARGETS LibPng
     EXPORT PDFHummusTargets
diff --git a/LibTiff/CMakeLists.txt b/LibTiff/CMakeLists.txt
index 02605c4d..f2825f9b 100644
--- a/LibTiff/CMakeLists.txt
+++ b/LibTiff/CMakeLists.txt
@@ -85,7 +85,12 @@ target_compile_definitions(LibTiff PUBLIC
     FILLODER_LSB2MSB=1
 )
 
-target_link_libraries(LibTiff PDFHummus::Zlib)
+if(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(LibTiff ZLIB::ZLIB)
+else(USING_UNBUNDLED_ZLIB)
+    target_link_libraries(LibTiff PDFHummus::Zlib)
+endif(USING_UNBUNDLED_ZLIB)
+
 
 if(WIN32 AND BUILD_SHARED_LIBS)
     set_target_properties(LibTiff PROPERTIES  WINDOWS_EXPORT_ALL_SYMBOLS ON)