diff --git a/c++/nda/blas/interface/cxx_interface.cpp b/c++/nda/blas/interface/cxx_interface.cpp
index 2c542257a..54c1ec39d 100644
--- a/c++/nda/blas/interface/cxx_interface.cpp
+++ b/c++/nda/blas/interface/cxx_interface.cpp
@@ -27,6 +27,7 @@
 #include <cstddef>
 
 #ifdef NDA_USE_MKL
+#include "../../basic_array.hpp"
 #include "../../declarations.hpp"
 
 #include <mkl.h>