(This is an entry in the Annotated Bibliography.)
Dreher, Denise. From the Neck Up: An Illustrated Guide to Hatmaking. Minneapolis: Madhatter Press, 1981.
This book is clearly a work of love, and an extremely thorough one, though geared more toward theatrical costuming that authentic historical. As an overall manual of millinery, it has an excellent reputation, and seems useful, though my familiarity with millinery is limited, so I cannot effectively review it in detail. However, the amount of detail offered is truly inspiring, such as all the different trim techniques offered. This is a promising resource on a topic that is increasingly obscure, recommended by a variety of historic costumers and books. It is instructional, including patterns. It contains monochrome images. It contains an extensive bibliography.