On all days during the Octave of All Saints (1-8 Nov.), a plenary indulgence, applicable only to the Poor Souls, is granted to those who visit a cemetery and pray, even if only mentally, for the departed. Partial indulgences are grated to those who recite Lauds or Vespers of the Office of the Dead and to those who recite the prayer “REQUIEM AETERNAM DONA EIS, DOMINI, ET LUX PERPETUA LUCEAT EIS. REQUIESANT IN PACE.” Conditions necessary for plenary indulgences to be acquired: (1) Sacramental confession, (2) Eucharistic Communion, and (3) prayer for the intention of the Sovereign Pontiff in addition to the performance of the work to which the indulgence is attached.
Original source can be found here.