Coulson, C.A.
Dictionary of pi-electron calculations
W.H. Freeman, 1965
 Buku Referensi
Imam Azis Kurnianto
Aplikasi kendali PI dalam pengendalian kecepatan putar motor BLDC = PI controller application for controlling rotation speed of BLDC
Fakultas Teknik Universitas Indonesia, 2013
 UI - Skripsi Membership
Wati Yulistiawati
Simulasi pengendali PI dan fuzzy-PI pada motor DC seri : Tugas seminar
Fakultas Teknik Universitas Indonesia, 1997
 UI - Tugas Akhir
Zhou, Yimin
Beijing qiao pi hua ci dian : Xiu ding ben
Yuwen Chubanshe, 2000
 Buku Teks
Pi, Ying-Hsien
Communist China's relations with East European Communist countries / Pi Ying-Hsein
World Anti-Communist League, 1986
 Buku Teks