1. Baines, P.: Penguin by Design: A Cover Story 1935–2005. Allen Lane, London (2005)
2. Drew, N., Sternberger, P.: By its Cover: Modern American Book Cover Design. Princeton Architectural Press, New York (2005)
3. Glass, D.: About Penguin: Company history. http://www.penguin.co.uk/static/cs/uk/0/aboutus/aboutpenguin_companyhistory.html
4. Howard, A., Gray, J., Pearson, D.: Gateways: Uma Exposição Internacional de Capas de Livros, Portugal/Gateways: an International Exhibition of Book Covers, Portugal. Fundação de Serralves, Porto (2008)
5. Powers, A.: Front Cover: Great Book Jacket and Cover Design. Octopus Publishing Group, London (2006)