diff --git a/README.adoc b/README.adoc
index d3bf73a..08a369c 100644
--- a/README.adoc
+++ b/README.adoc
@@ -102,9 +102,12 @@ of CMake.
 sudo apt install build-essential cmake libboost-program-options-dev \
                  libboost-locale-dev libboost-regex-dev libboost-log-dev \
                  gettext libarchive-dev libfmt-dev asciidoc libpugixml-dev \
-                  nlohmann-json3?-dev
+                 nlohmann-json-dev
 --------------------------------------------------------------------------------
 
+[NOTE]
+If `nlohmann-json-dev` can not be found, try nlohmann-json3-dev.
+
 ==== Get sourcecode
 
 ===== Release