diff --git a/src/math.jl b/src/math.jl
index 8fbd80c..df1e010 100644
--- a/src/math.jl
+++ b/src/math.jl
@@ -1,6 +1,7 @@
 # This file is a part of JuliaFEM.
 # License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
 
+using JuliaFEM
 using ForwardDiff
 
 """