Napitupulu, D. (2010). KPK in action. Raih Asa Sukses.
Lua i Stíl Chicago (17ú heag.)Napitupulu, Diana. KPK in Action. Raih Asa Sukses, 2010.
Lua MLA (8ú heag.)Napitupulu, Diana. KPK in Action. Raih Asa Sukses, 2010.
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