Fran92,
Google Dr. A.M.Pape, and look up the old pprune threads on subject.
Just as an aside, in recent times I have several reports of pilots who have failed an Ishihara in an office, (artificial light) who have passed when repeating the test in natural light.
Sadly, all ICAO requires is that you demonstrate your ability to "do the job", not demonstrate a particular standard of colour perception.
Tootle pip!!