diff --git a/packages/dubp_rs/README.md b/packages/dubp_rs/README.md
index fa2e785..305dcb4 100644
--- a/packages/dubp_rs/README.md
+++ b/packages/dubp_rs/README.md
@@ -7,11 +7,17 @@ Flutter package that bind [dubp-rs-libs] Rust crates.
 ### Prerequisites
 
 * Android SDK
-* Android NDK
+* Android **N**DK (**Native** Development Kit)
 * Rust and cargo
 * Cargo plugin cargo-make: `cargo install cargo-make`
 * LLVM/Clang (see dedicated section below)
 
+You must indicate where the SDK and NDK are located via the `ANDROID_SDK_ROOT` and `ANDROID_NDK_HOME` environment variables.
+For example:
+
+    export ANDROID_SDK_ROOT="/home/user/dev/android_sdk"
+    export ANDROID_NDK_HOME="/home/user/dev/android_sdk/ndk/22.0.7026061"
+
 You will also need to add targets for all Android architectures:
 
 ```sh