"The basis for this study was a series of articles ... syndicated to the newspapers in the year 1899 under the heading 'Tendencies in recent state constitutions'. In 1906 the articles were revised and published in the Galveston Daily news and the Dallas Morning news, and later were published as a pamphlet for general circulation. In 1907 the series was enlarged and published as a supplement number in the Annals of the American academy of social and political science, March, 1907." cf. Pref.
Bibliography, etc. Note
"General bibliography": pages 297-301.