Ellis, R. J. (1989). Dilemmas of presidential leadership: From Washington through Lincoln. Transaction.
Lua i Stíl Chicago (17ú heag.)Ellis, Richard J. Dilemmas of Presidential Leadership: From Washington Through Lincoln. New Brunswick, N.J: Transaction, 1989.
Lua MLA (9ú heag.)Ellis, Richard J. Dilemmas of Presidential Leadership: From Washington Through Lincoln. Transaction, 1989.
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