Visual etymological dictionary focusing on Persian, English and other Indo-European languages

This is my new favourite document on archive.org, a visual etymological dictionary with a focus on Persian and English common roots but with a number of other languages in there as well. Most full-length documents on archive.org are there because they are old and copyright-free, but this one is there due to being published under a Creative Commons license and the email address of the author is there as well.

To explain exactly how the format works, the best thing to do is simply show what one page of the dictionary looks like:

As you can see, it's the clean format with arrows that make this one so easy to read.

Is the dictionary 100% accurate? I have no idea. Perhaps Olivier will know.