APA (7th ed.) Citation

Sotheby & Co. (1949). Catalogue of valuable printed books and manuscripts, autograph letters .. Sotheby & Co.

Chicago Style (17th ed.) Citation

Sotheby & Co. Catalogue of Valuable Printed Books and Manuscripts, Autograph Letters .. London: Sotheby & Co, 1949.

MLA (9th ed.) Citation

Sotheby & Co. Catalogue of Valuable Printed Books and Manuscripts, Autograph Letters .. Sotheby & Co, 1949.

Warning: These citations may not always be 100% accurate.