http://www.aerovfr.com/2015/10/stabiliser-la-ligne-dhorizon/
http://www.iristab.fr/ et http://www.iristab.fr/Site%20Final/
[youtube https://www.youtube.com/watch?v=SmFvlXeuug4&w=560&h=315]
[youtube https://www.youtube.com/watch?v=0qcipkqIEeY&w=560&h=315]