Jackson, W. (1998). The four ages: Together with essays on various subjects. Thoemmes.
Chicago-viite (17. p.)Jackson, William. The Four Ages: Together with Essays on Various Subjects. Bristol: Thoemmes, 1998.
MLA-viite (8. p.)Jackson, William. The Four Ages: Together with Essays on Various Subjects. Thoemmes, 1998.
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