Update README.md

Author: termoshtt

README.md

@@ -2,10 +2,9 @@ ndarray-linalg
 ===============
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-
 Linear algebra package for Rust with [rust-ndarray](https://github.com/bluss/rust-ndarray).
 
 LAPACKE Backend
@@ -14,9 +13,11 @@ LAPACKE Backend
 Currently three LAPACKE implementations are supported and tested:
 
 - [OpenBLAS](https://github.com/cmr/openblas-src)
+  - needs `gfortran` (or other Fortran compiler)
 - [Netlib](https://github.com/cmr/netlib-src)
+  - needs `cmake` and `gfortran`
 - [Intel MKL](https://github.com/termoshtt/rust-intel-mkl) (non-free license, see the linked page)
-
+  - needs `curl`
 There are two ways to link LAPACKE backend:
 
 ### backend features (recommended)