Here’s a list of Scholarly Resources focusing on Historical Asian Fashions that is also available to English readers. Web sources are denoted as (WEB), public domain books available online as (ONLINE BOOK) , while the rest are printed books. Those with previews available on Google books are (PREVIEW ON GOOGLE BOOKS).
I have read most of these books/sources or have had them recommended to me. Some of these books may be out of print, but you may be able to find them at your local library (try Interloan).
More sources will be added as time goes by. Please let me know if you have a recommended source!
ASIA / WORLD
THAILAND / SIAM