I am trying to find a book about type design focusing on the process of designing a font. That is, since the catalyst or the idea, to the first primitive sketches, through the processes of adjusting and choosing the best forms for specific letters, designing alternates, etc. I am more interested in understanding how type designers "think" than the results they achieve.

Can any one point me in some direction?
After a quick search, I couldn't find any reference to such a book in Typophile.

Thank you!

(Thanks for the replies on the original thread, opened in the wrong forum, specially about this beauty. Hoping to get some more suggestions, still!)