Shankle, G. E. (1975). State names, flags, seals, songs, birds, flowers, and other symbols: A study based on historical documents giving the origin and significance of the state names, nicknames, mottoes, seals, flags, flowers, birds, songs, and descriptive comments on the capitol buildings and on some of the leading state histories, with facsimiles of the state flags and seals / by George Earlie Shankle (Rev. ed.). Greenwood Press.

Shankle, George Earlie. State Names, Flags, Seals, Songs, Birds, Flowers, and Other Symbols: A Study Based on Historical Documents Giving the Origin and Significance of the State Names, Nicknames, Mottoes, Seals, Flags, Flowers, Birds, Songs, and Descriptive Comments on the Capitol Buildings and on Some of the Leading State Histories, with Facsimiles of the State Flags and Seals / by George Earlie Shankle. Rev. ed. Westport, Conn.: Greenwood Press, 1975.

Shankle, George Earlie. State Names, Flags, Seals, Songs, Birds, Flowers, and Other Symbols: A Study Based on Historical Documents Giving the Origin and Significance of the State Names, Nicknames, Mottoes, Seals, Flags, Flowers, Birds, Songs, and Descriptive Comments on the Capitol Buildings and on Some of the Leading State Histories, with Facsimiles of the State Flags and Seals / by George Earlie Shankle. Rev. ed. Greenwood Press, 1975.