Cypripediums - Armacost & Royston.; Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Los Angeles, California, Armacost & Royston, Inc, 1949, 1949)
https://www.biodiversitylibrary.org/bibliography/188082
Keywords: California|Catalogs|Cypripedium|Los Angeles|Nursery stock|Orchids|Roots|Varieties|