Probably one of the most difficult tasks a self-trained perfumer has before them ~ all that research.
It isn't enough to read the right books or the books that someone who seems more experienced recommends. Bibliographies in those books are often recommended as great sources for further research (thanks Sara!), and often they are the flesh of the education. Obscure and out-of-print articles, all these materials need gathering. Not everything discovered, however, is worth the price of admission. Even in the days of all natural, lies and deceitfulness were circulating. No one was giving up trade secrets then either, not without a little sweat equity and emphasis on the importance of secrecy. The bottom line is don't believe everything to read on the subject.
Here's something that's useful in furthering the perfumer's education, but maybe not so useful in making a better perfumer.
'The Ancient Art of Perfumery' by John H. Snively
A Reprint of an Illustrated Article Originally Appearing in Harper's Magazine, 1874
'3,000 Year Old Egyptian Ointment at Alnwick Castle. Ottos, Alcoholates, and Tinctures. Plantations of Bitter Orange Trees. Orris, Tonka and Vanilla. Ambergris, Civet and Musk. Mixtures to Mimic difficult Flowers, Etc.'
Preservation Reprint #8079
Laurel Maryland USA
Cost of Admission: $7.50 plus $2.50 s&h to the US, $5.00 s&h Internationally