^ Lowell Barrington, Michael J. Bosia, Kathleen Bruhn, "Comparative Politics: Structures and Choices", Cengage Learning, 2009.
^ Lowell Barrington, Michael J. Bosia, Kathleen Bruhn, "Komperatibo a Politika: Dagiti Estruktura ken dagiti Pagpilian", Cengage Learning, 2009.