diff --git a/CMakeLists.txt b/CMakeLists.txt
index 365b835..4341de9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,7 @@ endif(JPEG_FOUND)
 include(FindJasper)
 if(JASPER_FOUND)
   set(HAVE_JASPER_LIB 1)
+  set(K2PDFOPT_LIB ${K2PDFOPT_LIB} ${JASPER_LIBRARY})
 endif(JASPER_FOUND)
 
 # paths from willuslib/wgs.c
@@ -71,9 +72,12 @@ else()
   message(STATUS "Could NOT find ghostscript executable")
 endif(GHOSTSCRIPT_EXECUTABLE)
 
-# willus.h
-# HAVE_GSL_LIB
-
+pkg_check_modules(GSL gsl)
+if(GSL_FOUND)
+  set(HAVE_GSL_LIB 1)
+  include_directories(SYSTEM ${GSL_INCLUDEDIR})
+  set(K2PDFOPT_LIB ${K2PDFOPT_LIB} ${GSL_LDFLAGS})
+endif(GSL_FOUND)
 
 # libfreetype6 (>= 2.3.9), libjbig2dec0, libjpeg8 (>= 8c), libx11-6, libxext6, zlib1g (>= 1:1.2.0)
 # MUPDF_STATIC_LDFLAGS misses mupdf-js-none, and doubles libs ...
@@ -85,7 +89,7 @@ if(MUPDF_FOUND)
   include_directories(SYSTEM ${MUPDF_INCLUDEDIR})
   message(STATUS "mupdf libraries: ${MUPDF_LDFLAGS}")
   set(K2PDFOPT_LIB ${K2PDFOPT_LIB} ${MUPDF_LDFLAGS} 
-    -lmupdf-js-none -lopenjpeg -ljbig2dec -ljpeg -lfreetype -llcms -lgumbo
+
   )
 endif(MUPDF_FOUND)