diff --git a/java-libs/README.postgresql-jar b/java-libs/README.postgresql-jar
new file mode 100644
index 0000000000000000000000000000000000000000..50eff7de0a7726529dbb324ec9ef278cd49b87fd
--- /dev/null
+++ b/java-libs/README.postgresql-jar
@@ -0,0 +1,16 @@
+
+
+postgresql-*.jar library should be loaded by tomcat: place it to its tomcat's classpath: .../tomcat/lib/
+
+Note access rights and ownership: tomcat:tomcat
+
+-rw-r-----. 1 tomcat tomcat 825943 Mar 23 08:03 /opt/tomcat/latest/lib/postgresql-42.2.5.jar
+
+also schema in URL access should be: jdbc:postgresql (not only postgresql://)
+
+jdbc:postgresql://127.0.0.1:5432/vialactea
+
+
+Manual: https://jdbc.postgresql.org/documentation/use/
+
+
diff --git a/java-libs/lib/postgresql-42.2.5.jar b/java-libs/postgresql-42.2.5.jar
similarity index 100%
rename from java-libs/lib/postgresql-42.2.5.jar
rename to java-libs/postgresql-42.2.5.jar