diff --git a/DockerSwarm/exercise.adoc b/DockerSwarm/exercise.adoc
index 0656096..571155a 100644
--- a/DockerSwarm/exercise.adoc
+++ b/DockerSwarm/exercise.adoc
@@ -82,8 +82,8 @@ image:swarmlab-network.png[alt="Vlab Network"]
 Η επιλογή project ανα ομάδα πρέπει να πραγματοποιηθεί μέχρι *03.05*
 ====
 
-===  Katex
-*  Katex
+===  Katex https://en.wikipedia.org/wiki/KaTeX[wikipedia]
+*  Katex - https://en.wikipedia.org/wiki/KaTeX, https://en.wikipedia.org/wiki/Mathematical_notation
 **  https://github.com/KaTeX/KaTeX
 **  https://katex.org/#demo
 
@@ -92,50 +92,56 @@ image:swarmlab-network.png[alt="Vlab Network"]
 **  https://github.com/gabidavila/docker-wordpress-ssl-nginx-mysql
 
 === mongo replicated
-*  mongo replicated
+*  mongo replicated -  https://en.wikipedia.org/wiki/MongoDB, https://github.com/mongodb/mongo/wiki/Replication-Internals , https://en.wikipedia.org/wiki/NoSQL
 **  https://www.xosofox.de/2017/06/running-mongodb-as-a-replicaset-in-docker/
 **  https://www.sohamkamani.com/blog/2016/06/30/docker-mongo-replica-set/#setting-up-replication
 
 === mysql replicated
-*  mysql replicated
+*  mysql replicated - https://en.wikipedia.org/wiki/Multi-master_replication
 **  https://github.com/gritt/docker-mysql-replication
 **  https://hub.docker.com/r/actency/docker-mysql-replication
 
 === asciidoc + online editor
-* asciidoc + online editor
+* asciidoc + online editor - https://en.wikipedia.org/wiki/AsciiDoc, https://en.wikipedia.org/wiki/DocBook
 **      https://github.com/bodiam/awesome-asciidoc
 **  https://github.com/asciidoctor/docker-asciidoctor
 
 === collaborative LaTeX editor
-* collaborative LaTeX editor
+* collaborative LaTeX editor - https://en.wikipedia.org/wiki/LaTeX
 **    https://github.com/overleaf/overleaf
 
 === Realtime database backend
-* Realtime database backend
+* Realtime database backend - https://en.wikipedia.org/wiki/Operational_transformation
 **    https://github.com/share/sharedb
 
 === collaborative editor (like google docs)
-* collaborative editor 
+* collaborative editor - https://en.wikipedia.org/wiki/CodeMirror
 **  https://github.com/hectorj2f/codemirror-dockerhttps://github.com/jitsi/docker-jitsi-meet
 **  https://codemirror.net/
 **  https://codemirror.net/mode/dockerfile/
 
 === hadoop
-* hadoop
+* hadoop - https://en.wikipedia.org/wiki/Apache_Hadoop
 **   https://github.com/big-data-europe/docker-hadoop
 **     https://hub.docker.com/r/sequenceiq/hadoop-docker/
 **     https://www.alibabacloud.com/blog/setup-a-single-node-hadoop-cluster-using-docker_595278
 
 === collaborative eclass meeting chat
-* collaborative eclass meeting chat
+* collaborative eclass meeting chat - https://en.wikipedia.org/wiki/Jitsi
 **     https://github.com/jitsi/docker-jitsi-meet
 
 === collaboration solution
-* collaboration solution
+* collaboration solution - https://en.wikipedia.org/wiki/Mattermost
 **   https://mattermost.com/mattermost-vs-slack/
 **     https://github.com/mattermost/mattermost-docker
 **     https://hub.docker.com/r/jasl8r/mattermost
 
+=== R and Octave (statistical computing and graphics)
+* R & Octave - https://en.wikipedia.org/wiki/R_(programming_language), https://en.wikipedia.org/wiki/GNU_Octave
+**   https://github.com/INWTlab/r-docker
+**   https://www.r-project.org/
+**   https://www.gnu.org/software/octave/
+
 === Ruby, php and Node.js
 * Ruby, php and Node.js
 **   https://hub.docker.com/r/ethanw93/docker-ruby-php-node/
@@ -146,12 +152,18 @@ image:swarmlab-network.png[alt="Vlab Network"]
 **    https://github.com/docker-java/docker-java
 
 === phonegap cordova
-* phonegap cordova
+* phonegap cordova  - https://en.wikipedia.org/wiki/Apache_Cordova
 **   https://hub.docker.com/r/webratio/phonegap/
 **    https://github.com/idotta/docker-phonegap
 **    https://github.com/oren/docker-cordova
 **    https://github.com/walterwhites/docker-cordova
 
+=== MuseScore + Lilypond (music engraving program)
+* MuseScore + Lilypond
+**   https://github.com/ericfont/MuseScore
+** http://lilypond.org/
+** https://musescore.org/en
+** https://github.com/markauskas/docker-lilypond
 
 == Q&A
 [qanda]