APA (7th ed.) Citation

Sotheby's (Firm). (1985). Postage stamps of the world. Sotheby.

Chicago Style (17th ed.) Citation

Sotheby's (Firm). Postage Stamps of the World. London: Sotheby, 1985.

MLA (9th ed.) Citation

Sotheby's (Firm). Postage Stamps of the World. Sotheby, 1985.

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