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Buku Referensi
Tooley, James
Continuum Studies Education Policy, 2000
Buku Teks
Fitria Nugrahani
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2015
UI - Tesis (Membership)
Smith, L. Glenn
Allyn and Bacon, 1973
Buku Teks
Williams, Gareth
PSI, [date of publication not identified]
Buku Teks