Cavaignac, _Histoire_, bk. iv, chs. ii, iv; Drumann-Groebe, _Geschichte
Roms in seiner Uebergange von der republicanischen zur monarchischen
Verfassung_, vol. ii, art. L. Cornelius Sulla; Ferrero, _Greatness and
Decline_, bk. i, chs. iii, iv, v; Frank, _Roman Imperialism_, chs. xii–xv;
Greenidge, _A History of Rome from 133 B. C.–69 A. D._ vol. i, to 104
B. C., Heitland, _Republic_, vol. ii, ch. xxxv–xlvii; Mommsen, _History_,
bk. iv, chs. i–ix; Niese, _Geschichte_, pp. 166–205; Oman, Ch., _Seven
Roman Statesmen_, chs. i–v, the Gracchi, Marius and Sulla.