APA (7th ed.) Citation

Sotheby & Co. (1949). Catalogue of a valuable library of printed books and mediaeval manuscripts .. Sotheby & Co.

Chicago Style (17th ed.) Citation

Sotheby & Co. Catalogue of a Valuable Library of Printed Books and Mediaeval Manuscripts .. London: Sotheby & Co, 1949.

MLA (9th ed.) Citation

Sotheby & Co. Catalogue of a Valuable Library of Printed Books and Mediaeval Manuscripts .. Sotheby & Co, 1949.

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