CoPA: Commercial Pattern Archive
The Commercial Pattern Archive database, CoPA, provides a unique tool for researchers and designers to recreate or date clothing from 1847 to present. Collections from the US, Canada and the UK are represented in the database which functions like a Union Catalog of pattern collections. The Pattern Archive is a project of the US Institute for Theatre Technology (USITT) Costume Commission. The cornerstone of CoPA is the Betty Williams Collection.
This is a free resource.