Comment by GoToRO

What I don't like are the "solutions" they propose: noise? use earplugs, light? use curtains. Well I will not be able to sleep if I have something in my ears and if you pull the curtains then you can no longer wake up naturally with the Sun. How about changing your lifestyle so that you can have silence and dark during the night and light in the morning without any "devices". You might have to quit your job :)