APA (7th ed.) Citation

Grosvenor, G., & Showalter, W. J. Flags of the world.

Chicago Style (17th ed.) Citation

Grosvenor, Gilbert, and William J. Showalter. Flags of the World. n.p.

MLA (8th ed.) Citation

Grosvenor, Gilbert, and William J. Showalter. Flags of the World.

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