1. Chapman, V.J.: Salt Marshes and Salt Deserts of the World, Ecology of Halophytes. Academic Press Inc., London, New York (1960)
2. Cap Atlantique: Discover and respect the SALT-MARSHES of the Guerande peninsula (2009).
http://www.cap-atlantique.fr/node/935
3. Cytron Technologies, Product Users Manual HC-SR04 Ultrasonic Sensor (2016)
4. Manuel Esteban Blog: Lire un capteur ultrason HC-SR04 avec un Raspberry Pi (2013).
http://www.manuel-esteban.com/lire-un-capteur-ultrason-hc-sr04-avec-un-raspberry-pi/
5. Tutorials Raspberrypi.com: Using a Raspberry Pi distance sensor (ultrasonic sensor HC-SR04) (2016).
https://tutorials-raspberrypi.com/raspberry-pi-ultrasonic-sensor-hc-sr04/