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README.md

 # Dockerfile for TeX Live 2019/2020
 
-This is a Dockerfile/Earthly repository of FULL TeX Live installation (but without src/doc/...).
+This is a Dockerfile/Earthly repository of FULL TeX Live installation (but
+without src/doc/...).
 
-# Usage
+The main repository is:
+- https://gitlab.inf.unibz.it/commul/docker/tools/texlive/
 
-## With `docker`
+The main (internal) container registry is:
+- https://gitlab.inf.unibz.it/commul/docker/tools/texlive/container_registry
+
+The (additional) external container registry is:
+- https://hub.docker.com/r/commul/texlive
+
+
+## Usage
+
+### With `docker`
 
 The working directory inside the container is **/docs** and the variable
 **$PWD** contains the path of the current directory.
@@ -17,7 +28,7 @@ docker run \
   pdflatex somedoc.tex
 ```
 
-## With `docker-compose`
+### With `docker-compose`
 
 The `docker-compose.yml` file defines a service `texlive` which can be used as follows:
 ```bash
@@ -30,7 +41,7 @@ The `docker-compose.yml` file defines a service `texlive-version` which can be u
 pdfTeX 3.14159265-2.6-1.40.20 (TeX Live 2019)
 ```
 
-## With `docker-compose` and `PATH`
+### With `docker-compose` and `PATH`
 
 With the `$(pwd)/bin` directory added to the `PATH` environment:
 ```bash
@@ -42,7 +53,7 @@ TEXLIVE_VERSION=2019 pdflatex --version
 ```
 
 
-# Build & update Docker images
+## Build & update Docker images
 
 ```bash
 # Clone git repository