bdul Baha ibn Baha Ullah. (1945). Foundations of world unity. Baha 'i Pub.Trust.
Cita Chicago (17th ed.)bdul Baha ibn Baha Ullah. Foundations of World Unity. Wilmette, Ill: Baha 'i Pub.Trust, 1945.
Cita MLA (9th ed.)bdul Baha ibn Baha Ullah. Foundations of World Unity. Baha 'i Pub.Trust, 1945.
Atenció: Aquestes cites poden no estar 100% correctes.