I glanced over Joseph Crane's article on archetypes, and saw he mentioned Dante's Divine Comedy.

I have in my posession a book that is IMO unsurpassed in its scope and breadth.
It is called "Dante's Christian Astrology" by Richard Kay.

Seldom have I read such a complete survey of planetary associations and subtle poetic referrals found in Dante's work, and the planetary symbolism explained and traced back to practically all the traditional authors (mostly - early - Arabic and medieval if I'm not mistaken).

I saw Amazon has a copy for sale, expensive, but worth it.

It sounds like an interesting book, Hermes. I don't have a copy, and the current used asking prices are so high that it's well down my list of priorities, but maybe a more affordable copy will appear at auction some day.

There have been several earlier works on astrological symbolism in Dante's Divine Comedy too. In fact, I came upon a review in JSTOR the other day criticising Richard Kay for giving scant attention to the observations they made previously. These were:

'Dantes Sternglaube' by Rudolf Palgen (1940);
'Der kosmische Aufbau der Jenseitsreiche Dantes' by Georg Rabuse (1958).
'Gesammelte Aufs?tze zu Dante' by Georg Rabuse (1976).

There was also a much earlier work in English that has been through several printings and is therefore more common second-hand than Richard Kay's more recent academic study:

'Dante's Ten Heavens: a Study of the Paradiso' by Edmund Gardner (first edition 1898; definitive second edition 1900; reprinted 1970).

For an astrologer wanting to make a special study of Dante, I would have thought that all the above works would be essential reading.